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BOOST pass an object to python code
by alex＠gorex.com.hk 16 Aug '07

16 Aug '07

Hello, I am new in this list. I would like to ask a quesiton about the linkage between BOOST and Python. I want to use C++ to trigger a Python code so that when I change anything inside Python, my C++ can know the changes and get the result back. So how can I pass an object from C++ to Python? and return the result? Here is the code that embedded the Class. class CppClass { public: int getNum() { return 7; } }; #include <boost/python.hpp> using namespace boost::python; int main( int argc, char ** argv ) { try { Py_Initialize(); object main_module(( handle<>(borrowed(PyImport_AddModule("__main__"))))); object main_namespace = main_module.attr("__dict__"); main_namespace["CppClass"] = class_<CppClass>("CppClass") .def("getNum",&CppClass::getNum); handle<> ignored(( PyRun_String( ""cpp = CppClass()\n" "print cpp.getNum()\n"", Py_file_input, main_namespace.ptr(), main_namespace.ptr() ) )); } catch( error_already_set ) { PyErr_Print(); } } Thanks

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[OT] Stroustrup video on slashdot
by Christian Henning 15 Aug '07

15 Aug '07

Hi there, some of you might be interested in watching his talk. http://it.slashdot.org/it/07/08/13/0818238.shtml I found this interview with Bjarne quite interesting: ----------- Interviewer: Well, it's been a few years since you changed the world of software design, how does it feel, looking back? Stroustrup: Actually, I was thinking about those days, just before you arrived. Do you remember? Everyone was writing 'C' and, the trouble was, they were pretty damn good at it. Universities got pretty good at teaching it, too. They were turning out competent - I stress the word 'competent' - graduates at a phenomenal rate. That's what caused the problem. Interviewer: Problem? Stroustrup: Yes, problem. Remember when everyone wrote Cobol? Interviewer: Of course, I did too Stroustrup: Well, in the beginning, these guys were like demi-gods. Their salaries were high, and they were treated like royalty. Interviewer: Those were the days, eh? Stroustrup: Right. So what happened? IBM got sick of it, and invested millions in training programmers, till they were a dime a dozen. Interviewer: That's why I got out. Salaries dropped within a year, to the point where being a journalist actually paid better. Stroustrup: Exactly. Well, the same happened with 'C' programmers. Interviewer: I see, but what's the point? Stroustrup: Well, one day, when I was sitting in my office, I thought of this little scheme, which would redress the balance a little. I thought 'I wonder what would happen, if there were a language so complicated, so difficult to learn, that nobody would ever be able to swamp the market with programmers? Actually, I got some of the ideas from X10, you know, X windows. That was such a bitch of a graphics system, that it only just ran on those Sun 3/60 things. They had all the ingredients for what I wanted. A really diculously complex syntax, obscure functions, and pseudo-OO structure. Even now, nobody writes raw X-windows code. Motif is the only way to go if you want to retain your sanity. Interviewer: You're kidding...? Stroustrup: Not a bit of it. In fact, there was another problem. Unix was written in 'C', which meant that any 'C' programmer could very easily become a systems programmer. Remember what a mainframe systems programmer used to earn? Interviewer: You bet I do, that's what I used to do. Stroustrup: OK, so this new language had to divorce itself from Unix, by hiding all the system calls that bound the two together so nicely. This would enable guys who only knew about DOS to earn a decent living too. Interviewer: I don't believe you said that... Stroustrup: Well, it's been long enough, now, and I believe most people have figured out for themselves that C++ is a waste of time but, I must say, it's taken them a lot longer than I thought it would. Interviewer: So how exactly did you do it? Stroustrup: It was only supposed to be a joke, I never thought people would take the book seriously. Anyone with half a brain can see that object-oriented programming is counter-intuitive, illogical and inefficient. Interviewer: What? Stroustrup: And as for 're-useable code' - when did you ever hear of a company re-using its code? Interviewer: Well, never, actually, but... Stroustrup: There you are then. Mind you, a few tried, in the early days. There was this Oregon company - Mentor Graphics, I think they were called - really caught a cold trying to rewrite everything in C++ in about '90 or '91. I felt sorry for them really, but I thought people would learn from their mistakes. Interviewer: Obviously, they didn't? Stroustrup: Not in the slightest. Trouble is, most companies hush-up all their major blunders, and explaining a $30 million loss to the shareholders would have been difficult. Give them their due, though, they made it work in the end. Interviewer: They did? Well, there you are then, it proves O-O works. Stroustrup: Well, almost. The executable was so huge, it took five minutes to load, on an HP workstation, with 128MB of RAM. Then it ran like treacle. Actually, I thought this would be a major stumbling-block, and I'd get found out within a week, but nobody cared. Sun and HP were only too glad to sell enormously powerful boxes, with huge resources just to run trivial programs. You know, when we had our first C++ compiler, at AT&T, I compiled 'Hello World', and couldn't believe the size of the executable. 2.1MB Interviewer: What? Well, compilers have come a long way, since then. Stroustrup: They have? Try it on the latest version of g++ - you won't get much change out of half a megabyte. Also, there are several quite recent examples for you, from all over the world. British Telecom had a major disaster on their hands but, luckily, managed to scrap the whole thing and start again. They were luckier than Australian Telecom. Now I hear that Siemens is building a dinosaur, and getting more and more worried as the size of the hardware gets bigger, to accommodate the executables. Isn't multiple eritance a joy? Interviewer: Yes, but C++ is basically a sound language. Stroustrup: You really believe that, don't you? Have you ever sat down and worked on a C++ project? Here's what happens: First, I've put in enough pitfalls to make sure that only the most trivial projects will work first time. Take operator overloading. At the end of the project, almost every module has it, usually, because guys feel they really should do it, as it was in their training course. The same operator then means something totally different in every module. Try pulling that lot together, when you have a red or so modules. And as for data hiding. God, I sometimes can't help laughing when I hear about the problems companies have making their modules talk to each other. I think the word 'synergistic' was specially invented to twist the knife in a project manager's ribs. Interviewer: I have to say, I'm beginning to be quite appalled at all this. You say you did it to raise programmers' salaries? That's obscene. Stroustrup: Not really. Everyone has a choice. I didn't expect the thing to get so much out of hand. Anyway, I basically succeeded. C++ is dying off now, but programmers still get high salaries - especially those poor devils who have to maintain all this crap. You do realise, it's impossible to maintain a large C++ software module if you didn't actually write it? Interviewer: How come? Stroustrup: You are out of touch, aren't you? Remember the typedef? Interviewer: Yes, of course. Stroustrup: Remember how long it took to grope through the header files only to find that 'RoofRaised' was a double precision number? Well, imagine how long it takes to find all the implicit typedefs in all the Classes in a major project. Interviewer: So how do you reckon you've succeeded? Stroustrup: Remember the length of the average-sized 'C' project? About 6 months. Not nearly long enough for a guy with a wife and kids to earn enough to have a decent standard of living. Take the same project, design it in C++ and what do you get? I'll tell you. One to two years. Isn't that great? All that job security, just through one mistake of judgement. And another thing. The universities haven't been teaching 'C' for such a long time, there's now a shortage of decent 'C' programmers. Especially those who know nything about Unix systems programming. How many guys would know what to do with 'malloc', when they've used 'new' all these years - and never bothered to check the return code. In fact, most C++ programmers throw away their return codes. Whatever happened to good ol' '-1'? At least you knew you had an error, without bogging the thing down in all that 'throw' 'catch' 'try' stuff. Interviewer: But, surely, inheritance does save a lot of time? Stroustrup: Does it? Have you ever noticed the difference between a 'C' project plan, and a C++ project plan? The planning stage for a C++ project is three times as long. Precisely to make sure that everything which should be inherited is, and what shouldn't isn't. Then, they still get it wrong. Whoever heard of memory leaks in a 'C' program? Now finding them is a major industry. Most companies give up, and send the product out, knowing it leaks like a sieve, simply to avoid the expense of tracking them all down. Interviewer: There are tools... Stroustrup: Most of which were written in C++. Interviewer: If we publish this, you'll probably get lynched, you do realise that? Stroustrup: I doubt it. As I said, C++ is way past its peak now, and no company in its right mind would start a C++ project without a pilot trial. That should convince them that it's the road to disaster. If not, they deserve all they get. You know, I tried to convince Dennis Ritchie to rewrite Unix in C++. Interviewer: Oh my God. What did he say? Stroustrup: Well, luckily, he has a good sense of humor. I think both he and Brian figured out what I was doing, in the early days, but never let on. He said he'd help me write a C++ version of DOS, if I was interested. Interviewer: Were you? Stroustrup: Actually, I did write DOS in C++, I'll give you a demo when we're through. I have it running on a Sparc 20 in the computer room. Goes like a rocket on 4 CPU's, and only takes up 70 megs of disk. Interviewer: What's it like on a PC? Stroustrup: Now you're kidding. Haven't you ever seen Windows '95? I think of that as my biggest success. Nearly blew the game before I was ready, though. Interviewer: You know, that idea of a Unix++ has really got me thinking. Somewhere out there, there's a guy going to try it. Stroustrup: Not after they read this interview. Interviewer: I'm sorry, but I don't see us being able to publish any of this. Stroustrup: But it's the story of the century. I only want to be remembered by my fellow programmers, for what I've done for them. You know how much a C++ guy can get these days? Interviewer: Last I heard, a really top guy is worth $70 - $80 an hour. Stroustrup: See? And I bet he earns it. Keeping track of all the gotchas I put into C++ is no easy job. And, as I said before, every C++ programmer feels bound by some mystic promise to use every damn element of the language on every project. Actually, that really annoys me sometimes, even though it serves my original purpose. I almost like the language after all this time. Interviewer: You mean you didn't before? Stroustrup: Hated it. It even looks clumsy, don't you agree? But when the book royalties started to come in... well, you get the picture. Interviewer: Just a minute. What about references? You must admit, you improved on 'C' pointers. Stroustrup: Hmm. I've always wondered about that. Originally, I thought I had. Then, one day I was discussing this with a guy who'd written C++ from the beginning. He said he could never remember whether his variables were referenced or dereferenced, so he always used pointers. He said the little asterisk always reminded him. Interviewer: Well, at this point, I usually say 'thank you very much' but it hardly seems adequate. Stroustrup: Promise me you'll publish this. My conscience is getting the better of me these days. Interviewer: I'll let you know, but I think I know what my editor will say. Stroustrup: Who'd believe it anyway? Although, can you send me a copy of that tape? Interviewer: I can do that.

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Having trouble with boost thread library
by Fei Liu 15 Aug '07

15 Aug '07

#ifndef UTILS_NETWORK_TCP_CONNECTION_HPP #define UTILS_NETWORK_TCP_CONNECTION_HPP namespace utils{ namespace thread{ template <typename shared_obj_type, typename thread_pool_type, typename serverlet_type> class tcp_connection{ private: int newsockfd; shared_obj_type obj; thread_pool_type pool; serverlet_type serverlet; bool initialized_; public: tcp_connection() : initialized_ (false) {} tcp_connection(int newsockfd, shared_obj_type obj, thread_pool_type pool, serverlet_type serverlet) : newsockfd(newsockfd), obj(obj), pool(pool), serverlet(serverlet), initialized_(true) { } bool initialized() { return initialized_; } bool initialize(int newsockfd, shared_obj_type obj, thread_pool_type pool, serverlet_type serverlet); void operator ()(); }; template <typename shared_obj_type, typename thread_pool_type, typename serverlet_type> bool tcp_connection<shared_obj_type, thread_pool_type, serverlet_type>::initialize (int newsockfd, shared_obj_type obj, thread_pool_type pool, serverlet_type serverlet) { this->newsockfd = newsockfd; this->obj = obj; this->pool = pool; this->serverlet = serverlet; initialized_ = true; return initialized_; } template <typename shared_obj_type, typename thread_pool_type, typename serverlet_type> void tcp_connection<shared_obj_type, thread_pool_type, serverlet_type>::operator() () { //if(initialized_) serverlet_type(newsockfd, obj); <---- causes error pool->release(); } } } #endif main.cpp: provides definition of serverlet_type #include "utils/thread/tcp_server.hpp" #include "utils/thread/thread_pool.h" #include <boost/shared_ptr.hpp> #include <vector> #include <iostream> typedef std::vector<int> shared_obj_type; typedef boost::shared_ptr<boost_thread::thread_pool> thread_pool_type; typedef void (*serverlet_type)(int, shared_obj_type); void servlet(int sock, shared_obj_type ){ std::cout << "got a new socket for a new connection: " << sock << std::endl; } int main(){ shared_obj_type x; thread_pool_type p( new boost_thread::thread_pool(20) ); utils::thread::tcp_server<shared_obj_type, thread_pool_type, serverlet_type> server; server.initialize(x, p, servlet, 10000, 5); boost::thread s(server); s.join(); } /root/cpp-utils-header-lib/include/utils/thread/tcp_connection.hpp: In member function `void utils::thread::tcp_connection<shared_obj_type, thread_pool_type, serverlet_type>::operator()() [with shared_obj_type = shared_obj_type, thread_pool_type = thread_pool_type, serverlet_type = void (*)(int, shared_obj_type)]': /usr/include/boost/function/function_template.hpp:155: instantiated from `static void boost::detail::function::void_function_obj_invoker0<FunctionObj, R>::invoke(boost::detail::function::function_buffer&) [with FunctionObj = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void]' /usr/include/boost/function/function_template.hpp:368: instantiated from `void boost::detail::function::basic_vtable0<R, Allocator>::init(FunctionObj, boost::detail::function::function_obj_tag) [with FunctionObj = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:298: instantiated from `void boost::detail::function::basic_vtable0<R, Allocator>::init(F) [with F = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:277: instantiated from `boost::detail::function::basic_vtable0<R, Allocator>::basic_vtable0(F) [with F = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:655: instantiated from `void boost::function0<R, Allocator>::assign_to(Functor) [with Functor = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:513: instantiated from `boost::function0<R, Allocator>::function0(Functor, typename boost::enable_if_c< boost::type_traits::ice_not< boost::is_integral<Functor>::value>::value, int>::type) [with Functor = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /root/cpp-utils-header-lib/include/utils/thread/tcp_server.hpp:107: instantiated from `void utils::thread::tcp_server<shared_obj_type, thread_pool_type, serverlet_type, accept_fail_policy>::operator()() [with shared_obj_type = shared_obj_type, thread_pool_type = thread_pool_type, serverlet_type = void (*)(int, shared_obj_type), accept_fail_policy = utils::thread::default_accept_fail_policy]' /usr/include/boost/function/function_template.hpp:155: instantiated from `static void boost::detail::function::void_function_obj_invoker0<FunctionObj, R>::invoke(boost::detail::function::function_buffer&) [with FunctionObj = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void]' /usr/include/boost/function/function_template.hpp:368: instantiated from `void boost::detail::function::basic_vtable0<R, Allocator>::init(FunctionObj, boost::detail::function::function_obj_tag) [with FunctionObj = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:298: instantiated from `void boost::detail::function::basic_vtable0<R, Allocator>::init(F) [with F = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:277: instantiated from `boost::detail::function::basic_vtable0<R, Allocator>::basic_vtable0(F) [with F = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:655: instantiated from `void boost::function0<R, Allocator>::assign_to(Functor) [with Functor = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:513: instantiated from `boost::function0<R, Allocator>::function0(Functor, typename boost::enable_if_c< boost::type_traits::ice_not< boost::is_integral<Functor>::value>::value, int>::type) [with Functor = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' tests/boost_tcp_server_test.cpp:24: instantiated from here /root/cpp-utils-header-lib/include/utils/thread/tcp_connection.hpp:61: error: functional cast expression list treated as compound expression /root/cpp-utils-header-lib/include/utils/thread/tcp_connection.hpp:61: warning: left-hand operand of comma has no effect /root/cpp-utils-header-lib/include/utils/thread/tcp_connection.hpp:61: error: cannot convert `((void)((utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>*)this)->utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>::newsockfd, ((utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>*)this)->utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>::obj)' from type `shared_obj_type' to type `void (*)(int, shared_obj_type)'

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Update: application failed to initialize, bad jmp to malloc?
by David Daeschler 15 Aug '07

15 Aug '07

I'm sorry this post is so long, I'm looking for someone who may have experienced this, or knows enough about what I am rambling about to help me. I haven't been able to run our app built with MINGW for a week now, and It's starting to become a problem. This is a followup to a previous post entitled "Wrong DLL init routine being called?". I am starting a new post because it appears as if the stack traces I was getting before were wrong. I now have more information, and feel I am closer to solving this. When I try to load a test application I'm receiving the message: "The application failed to initialize properly (0xc0000005). Click on OK to terminate the application." I am not using auto-imports, so solutions referring to them have not helped me. I have always been winding up in malloc during the crashes I've been experiencing in calls to DLL initialization routines. I've been able to get a stack trace that lands up inside dllcrt1.c (the STATIC MINGW runtime) and shows me which call to malloc is segfaulting. The stack trace is as follows: #0 0x003e14a0 in malloc () #1 0x003e111c in DllMainCRTStartup@12 (hDll=0x3e0000, dwReason=1, lpReserved=0x22fd30) at dllcrt1.c:56 #2 0x7c9011a7 in ntdll!LdrSetAppCompatDllRedirectionCallback () from C:\WINDOWS\system32\ntdll.dll #3 0x003e0000 in ?? () #4 0x00000001 in ?? () #5 0x003e10c0 in __dll_exit () at dllcrt1.c:149 #6 0x00000000 in ?? () with frame 1 (inside dllcrt1.c) as: (gdb) f 1 #1 0x003e111c in DllMainCRTStartup@12 (hDll=0x3e0000, dwReason=1, lpReserved=0x22fd30) at dllcrt1.c:56 56 first_atexit = (p_atexit_fn*) malloc (32 * sizeof (p_atexit_fn)); Current language: auto; currently c (gdb) list 51 #endif 52 53 /* Initialize private atexit table for this dll. 54 32 is min size required by ANSI */ 55 56 first_atexit = (p_atexit_fn*) malloc (32 * sizeof (p_atexit_fn)); 57 if (first_atexit == NULL ) /* can't allocate memory */ 58 { 59 errno=ENOMEM; 60 return FALSE; Notice line 56. It seems innocent enough, how could a call to malloc be crashing? Well I called malloc from insidge gdb, and it worked fine, so I then dug further in and noticed that the malloc symbol that gdb is seeing is: (gdb) print malloc $1 = {<text variable, no debug info>} 0x40c780 <malloc> 0x40c780, okay, lets see a disassembly: Dump of assembler code for function malloc: 0x0040c780 <malloc+0>: jmp *0x41b1dc So there is a jump to 0x41b1dc, sure enough that lands us inside of: (gdb) disas 0x41b1dc Dump of assembler code for function _imp__malloc: 0x0041b1dc <_imp__malloc+0>: pop %es 0x0041b1dd <_imp__malloc+1>: les (bad),%eax 0x0041b1de <_imp__malloc+2>: ret $0x77 Ahh, import stub that leads us to: (gdb) disas _imp__malloc Dump of assembler code for function msvcrt!malloc: 0x77c2c407 <msvcrt!malloc+0>: mov %edi,%edi 0x77c2c409 <msvcrt!malloc+2>: push %ebp 0x77c2c40a <msvcrt!malloc+3>: mov %esp,%ebp 0x77c2c40c <msvcrt!malloc+5>: cmpl $0x0,0x77c62418 0x77c2c413 <msvcrt!malloc+12>: jne 0x77c2c420 <msvcrt!malloc+25> 0x77c2c415 <msvcrt!malloc+14>: call 0x77c1ef38 <msvcrt!__initenv+77> 0x77c2c41a <msvcrt!malloc+19>: test %eax,%eax 0x77c2c41c <msvcrt!malloc+21>: jne 0x77c2c420 <msvcrt!malloc+25> 0x77c2c41e <msvcrt!malloc+23>: pop %ebp 0x77c2c41f <msvcrt!malloc+24>: ret 0x77c2c420 <msvcrt!malloc+25>: pushl 0x77c61808 0x77c2c426 <msvcrt!malloc+31>: pushl 0x8(%ebp) 0x77c2c429 <msvcrt!malloc+34>: call 0x77c2c3d4 <msvcrt!free+441> 0x77c2c42e <msvcrt!malloc+39>: pop %ecx 0x77c2c42f <msvcrt!malloc+40>: pop %ecx 0x77c2c430 <msvcrt!malloc+41>: pop %ebp 0x77c2c431 <msvcrt!malloc+42>: ret 0x77c2c432 <msvcrt!malloc+43>: int3 0x77c2c433 <msvcrt!malloc+44>: int3 0x77c2c434 <msvcrt!malloc+45>: int3 0x77c2c435 <msvcrt!malloc+46>: int3 0x77c2c436 <msvcrt!malloc+47>: int3 End of assembler dump. Good, this is where I would expect to be, right at home inside of msvcrt. But now take a look at the first frame of our original stack trace. #0 0x003e14a0 in malloc () 0x3e14a0.. Umm, hmmm, wierd. Let's see where that leads us? (gdb) disas 0x3e14a0 Dump of assembler code for function malloc: 0x003e14a0 <malloc+0>: jmp *0x90c0609c I'd hate to say it, but there is no 0x90x0609c. That explains the segfault. Let's see what else is around 0x3e14a0... (gdb) disas 0x3e1490 Dump of assembler code for function _pei386_runtime_relocator: 0x003e1470 <_pei386_runtime_relocator+0>: mov $0x90c03034,%ecx 0x003e1475 <_pei386_runtime_relocator+5>: push %ebp 0x003e1476 <_pei386_runtime_relocator+6>: cmp $0x90c03034,%ecx 0x003e147c <_pei386_runtime_relocator+12>: mov %esp,%ebp 0x003e147e <_pei386_runtime_relocator+14>: jae 0x3e1498 <_pei386_runtime_relocator+40> 0x003e1480 <_pei386_runtime_relocator+16>: mov 0x4(%ecx),%edx 0x003e1483 <_pei386_runtime_relocator+19>: mov (%ecx),%eax 0x003e1485 <_pei386_runtime_relocator+21>: add $0x8,%ecx 0x003e1488 <_pei386_runtime_relocator+24>: add $0x90c00000,%edx 0x003e148e <_pei386_runtime_relocator+30>: add %eax,(%edx) 0x003e1490 <_pei386_runtime_relocator+32>: cmp $0x90c03034,%ecx 0x003e1496 <_pei386_runtime_relocator+38>: jb 0x3e1480 <_pei386_runtime_relocator+16> 0x003e1498 <_pei386_runtime_relocator+40>: pop %ebp 0x003e1499 <_pei386_runtime_relocator+41>: ret End of assembler dump. That looks like static libgcc to me. So is libgcc calling the wrong malloc for some reason? Why? Is this a relocation problem? Is there any way I can fix this? Is there anyone else I should be asking? I am using the dwarf2 GCC 4.2.1, but I had the same results with gcc 3.4.5 (though with less details on the crash) I was thinking that maybe shared libgcc would fix my problem, but I can't seem to link with it. When I specify -shared-libgcc it says I'm missing libgcc_s.a which I can't find anywhere. Details on my setup: $ gcc -v Using built-in specs. Target: mingw32 Configured with: ../gcc-4.2.1-2-src/configure --with-gcc --enable-libgomp --host=mingw32 --build=mingw32 --target=mingw32 --program-suffix=-dw2 --with-arch=i486 --with-tune=generic --disable-werror --prefix=/mingw --with-local-prefix=/mingw --enable-threads --disable-nls --enable-languages=c,c ++,fortran,objc,obj-c++,ada --disable-win32-registry --disable-sjlj-exceptions --enable-libstdcxx-debug --enable-cxx-flags=-fno-function-sections -fno-data-sections --enable-version-specific-runtime-libs --disable-bootstrap Thread model: win32 gcc version 4.2.1-dw2 (mingw32-2) $ld -v GNU ld version 2.17.50 20060824 MINGW runtime is a debug compiled version of mingw-runtime-3.13

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BOOST_NO_IS_ABSTRACT defined for SunPRO CC?
by Sohail Somani 15 Aug '07

15 Aug '07

Hi, In the upgrade to boost 1.34.1, I noticed that the sunpro_cc.hpp config file now defines BOOST_NO_IS_ABSTRACT for the latest compiler. This affects serialization code that used to work with 1.33.1. The relevant change is here: http://svn.boost.org/trac/boost/changeset/32005 I'm wondering, why was this change made since it seems to work? There is no ticket referenced in the commit. Thanks, Sohail

2 3

[program_options] Short program options
by Christian Henning 15 Aug '07

15 Aug '07

Hi there, a while ago I was asking some questions about the short option feature. If I'm not mistaken a short option can only be one letter long. Is that correct to say? In my project I need more than this. So I started to just add the short names to the options list like I would do for all options. But in this case they would share the same variable. Like this: po::options_description settings( "" ); settings.add_options() ( "input_1" , po::value< string >( &_input ) ->default_value( "" ) , "" ) ( "i1" , po::value< string >( &_input ) ->default_value( "" ) , "" ); Both options are pointing to the same variable. For some reasons this code works only for "input_1" and not for "i1". Why is that? If I use --i1="Hallo" the _input is empty. Regards, Christian

3 3

asio's io_service uses too many file descriptors
by pete＠mu.org 15 Aug '07

15 Aug '07

I posted this under a less suitable subject line a week ago, but I got no response. I hope the above live will trigger some help. I 've been doinking around with asio for a few weeks, and I've run into an issue I can't seem to wrap my head around. I've been playing with some code that originally was meant to pound a server with a large amount of packets for benchmarking purposes. It uses threads to launch hundreds of threads per second. When I replaced the old socket code with asio, and used a single io_service with run being called within each thread, I run out of file descriptors very quickly, and if I use a single io_service within each thread it's the same thing but the performance seems worse. Needless to say, this seems like a real limitation and I'm hoping I'm just being limited by my own misunderstanding, because I'm really enjoying the portability of asio. The docs that are there seem great, but there seems to be a lot more the library can do that I am missing out on, and I think the docs seem like they are not mentioning a lot of what asio an do. Can someone point me in the right direction for launching 1-to-N threads with a single send_to and a single receive_from within each thread that doesn't take the hit I'm seeing? It seems to me, that it's obvious that the io-service design is the difference, because I don't get the issue at all when I use plain old sockets, and the OS thread limit is then the only limitation. Any help would be greatly appreciated. FYI, I've done most of my experimenting on Linux and OSX. I can send some code samples if needed, but I think the problem should be apparent if anyone else has tried to use asio with large amounts of threads. Thanks, Pete

3 4

boost serialization excessive warning messages
by Fei Liu 15 Aug '07

15 Aug '07

Hi Group, I am getting multiple warning messages like the following from boost serialization library: /usr/include/boost/archive/detail/iserializer.hpp:124: warning: unused parameter 'flags' I am pretty sure this is a common issue but I haven't found any clue through the web. Is there a way to turn off the warning through proper coding? I am using gcc on linux. Fei

5 11

[iostreams] Different character type in a filtering stream [C1]
by frederic.mayot＠sgcib.com 15 Aug '07

15 Aug '07

Hi, I'd like to create a pipeline composed of filters that have different input and output character type. For example: file -> | Source | -> char -> | F1 | -> message -> | F2 | where F1 and F2 are input filters. F1 can be kind of a parser that would cut the stream into messages. The thing is that I could always rewrite a file_source but I think it's not a good design. What would you suggest? Thanks, ____________________________ Frederic MAYOT Société Générale - Equity IT 1221 Avenue of the Americas New York, NY 10020 +1 (212) 278-5558 +1 (917) 673-1339 ************************************************************************* This message and any attachments (the "message") are confidential and intended solely for the addressees. Any unauthorised use or dissemination is prohibited. E-mails are susceptible to alteration. Neither SOCIETE GENERALE nor any of its subsidiaries or affiliates shall be liable for the message if altered, changed or falsified. *************************************************************************

1 0

Using cross-compiler to build the libraries
by Bruce Reid 15 Aug '07

15 Aug '07

I have been able to build (and link with) the libraries using the native gcc compiler on my linux-x86 platform, but have been unable to find a way to force the build process to use something like: /path/to/my/cross_compiler/for/linux-ppc/gcc Can someone please advise me in the proper way to build the libs with an absolute path to my cross compiler? Thanks very much for any help, Bruce CONFIDENTIALITY NOTICE: This email, together with any attachments, is intended only for use by Aristos Logic Corporation and the individual(s) to which it is addressed and may contain information that is privileged, confidential or exempt from disclosure. If you are not the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this email, or any attachment, is strictly prohibited. If you have received this email in error, please notify Aristos Logic Corporation by sending an email to sysadm(a)aristoslogic.com and delete this email, along with any attachments, from your computer. Thank you.

2 1

boost filesystem undefined reference...
by chun ping wang 15 Aug '07

15 Aug '07

./myfile/lib/libmy.a(my.o): In function `ZN4My6My_t4initERKNS0_10Settings_tE': C:/Boost/include/boost-1_34_1/boost/filesystem/path.hpp:302: undefined reference to `boost::filesystem::detail::status_api(std::string const&, unsigned int&)' ./myfile/lib/libmy.a(my.o): In function `_tcf_0': C:/CPW/cs_classes/./myfile/include/myerror.h:186: undefined reference to `boost::filesystem::detail::get_current_path_api(std::string&)' i build boost linking to a built boost filesystem file using mingw 3.4.5 including option. -l"boost_filesystem-mgw34-1_34_1" this is line 302 of path.hpp "const external_string_type external_file_string() const { return Traits::to_external( *this, file_string() ); }" "

1 0

Searching through a vector of tuples...
by Graham Reitz 15 Aug '07

15 Aug '07

typedef boost::tuples::tuple<int,double> some_tuple; std::vector<some_tuple> vec_of_some_tuples; // ... stuff some data into the vector // ... search for a specific int in the vector of some_tuple What would be a good method, using an stl algorithm, to search through the vector above to match only the int portion of the tuple (ignoring the double)? Thanks, Graham

4 4

boost.test and independent compilation/running of tests
by Alexander Schmolck 15 Aug '07

15 Aug '07

Hi, I'm trying to figure out what the best way to use boost.test to achieve something close to TDD (test driven development) is; I should presumably also mention that I'm using qmake and not bjam as a build utility. I've managed to build and use boost.test fine (after figuring out that I needed to add -DBOOST_TEST_DYN_LINK), but what I haven't been able to achieve is to a) have several smaller test-cases/suites for TDD so that I can rapidly recompile and run a small subset of tests whilst I'm developing a specific class. b) have one big test-suite, integrating all the above, for regression testing to be run periodically (after the above subset of tests passed; on svn commit etc.) I haven't figured out how to set things up so that I can compile individual tests to .o files and then either simply build a complete regression suite executable from them or an executable from just one (or a few) of these tests; because I don't know how to use the autoregistration facilities without ending up with multiple main()s. My test files currently look something like this: //file foo_test.cpp #define BOOST_TEST_MODULE foo_test #include <boost/test/unit_test.hpp> #include "foo.h" // Test Suite BOOST_AUTO_TEST_SUITE(foo_test_suite); BOOST_AUTO_TEST_CASE(some_test_case) { // ... } BOOST_AUTO_TEST_SUITE_END(); What's the recommended way to go about this? thanks, 'as

2 3

hash_multimap serialization issue
by Lorenzo Cavallaro 15 Aug '07

15 Aug '07

Dear Boost list, I'm trying to use the boost serialization class to serialize some objects. Unfortunately, I keep running into the same issue (compilation error) that I report here below for clarity $ g++-3.4 -fPIC -O2 -g -I. -c model.cpp -o model.o /usr/include/boost/serialization/access.hpp: In static member function +`static void boost::serialization::access::serialize(Archive&, T&, unsigned +int) [with Archive = boost::archive::text_oarchive, T = +__gnu_cxx::hash_multimap<addr_t, Events*, __gnu_cxx::hash<unsigned int>, +eqaddr, std::allocator<Events*> >]': /usr/include/boost/serialization/serialization.hpp:81: instantiated from `void +boost::serialization::serialize(Archive&, T&, unsigned int) [with Archive = +boost::archive::text_oarchive, T = __gnu_cxx::hash_multimap<addr_t, Events*, +__gnu_cxx::hash<unsigned int>, eqaddr, std::allocator<Events*> >]' /usr/include/boost/serialization/serialization.hpp:140: instantiated from +`void boost::serialization::serialize_adl(Archive&, T&, unsigned int) [with +Archive = boost::archive::text_oarchive, T = __gnu_cxx::hash_multimap<addr_t, +Events*, __gnu_cxx::hash<unsigned int>, eqaddr, std::allocator<Events*> >]' /usr/include/boost/archive/detail/oserializer.hpp:148: instantiated from `void +boost::archive::detail::oserializer<Archive, +T>::save_object_data(boost::archive::detail::basic_oarchive&, const void*) +const [with Archive = boost::archive::text_oarchive, T = +__gnu_cxx::hash_multimap<addr_t, Events*, __gnu_cxx::hash<unsigned int>, +eqaddr, std::allocator<Events*> >]' model.cpp:599: instantiated from here /usr/include/boost/serialization/access.hpp:109: error: 'class +__gnu_cxx::hash_multimap<addr_t, Events*, __gnu_cxx::hash<unsigned int>, +eqaddr, std::allocator<Events*> >' has no member named 'serialize' make: *** [model.o] Error 1 I've looked for this error on Internet and I found out that a discussion on the boost mailing list dated back on 2005 (http://lists.boost.org/boost-users/2005/08/13183.php) I tried making those changes but nothing happened and I still have the reported compilation error. For the sake of clarity, here's a snippet of the code I'm trying to compile #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/utility.hpp> #include <boost/serialization/list.hpp> #include <boost/serialization/vector.hpp> #include <boost/serialization/hash_map.hpp> #include <ext/hash_map> using namespace std; using namespace __gnu_cxx; struct eqaddr { bool operator()(addr_t ret1, addr_t ret2) const { return ret1 == ret2; } }; typedef hash_multimap<addr_t, Events *, hash<addr_t>, eqaddr> model_t; class ModelMap { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int file_version) { ar & map; } public: model_t map; ModelMap() { } ~ModelMap() { } }; I'm using libboost-serialization 1.33.1-10 (debian) Any idea on how to fix this? Am I doing something wrong? TIA, bye Lorenzo -- Lorenzo `Gigi Sullivan' Cavallaro <sullivan(a)security.dico.unimi.it> GPG key at http://security.dico.unimi.it/~sullivan/sullivan.asc Until I loved, life had no beauty; I did not know I lived until I had loved. (Theodor Korner) See the reality in your eyes, when the hate makes you blind. (A.H.X)

1 0

How to import a dll to python
by desai3＠cooper.edu 14 Aug '07

14 Aug '07

Hi all: I am completely new to Python and Boost.python. (I have been using it for two days) I was trying out a tutorial example that is located in the boost_1_34_1\libs\example\tutorial folder of the standard Boost distribution. After running ./Bjam target-os=cygwin toolset = gcc it created hello.dll, hello.dll.a and hello.o files in boost_1_34_1\libs\python\example\tutorial\bin\gcc-3.4.4\debug. However, when I go to python and use "import python" it gives me following error ######################################## Traceback (most recent call last): File "<stdin>", line 1, in <module> ImportError: No module named hello ######################################## What am I doing wrong? I am completely new to this boost and python so simplified answers will help a lot. Thank you

2 3

any_cast on polymoprhic types?
by Gross, Steve 14 Aug '07

14 Aug '07

Is there a way to use any_cast for polymorphic types? For instance, let's say I've got a Base class and a Derived class. I want to be able to any_cast a Derived * to a Base * successfully, like so: class Base { virtual ~Base() {} }; class Derived : public Base { virtual ~Derived() {} }; Derived d; boost::any a = &d; boost::any_cast<Base*>(a); // Will NOT throw an exception Thanks! --Steve

1 0

ptr_map<int, T> where T has no default constructor because its private members are const
by e r 14 Aug '07

14 Aug '07

hi, i can build a map<int,A*>, but not a boost::ptr_map<unsigned int,A>. could someone please help? thank you, e. #include <boost/ptr_container/ptr_map.hpp> using std::map; using std::cout; using std::endl; class A{ public: A(double x_):x(x_){}; const double x; }; int main(){ map<int,A*> map_A; //cannot use map<int,A> //because A() not defined //why? because A has const members. A a(0.0); map_A[0]=new A(0.0);//fine boost::ptr_map<unsigned int,A> ptr_map_A; ptr_map_A[0]=new A(0.0);//not fine return 0; }; **** Build of configuration Debug for project testing_map **** make -k all Building file: ../main.cpp Invoking: GCC C++ Compiler g++ -I/usr/local/boost_1_34_1 -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"main.d" -MT"main.d" -o"main.o" "../main.cpp" ../main.cpp:25:3: warning: no newline at end of file ../main.cpp: In function ‘int main()’: ../main.cpp:22: error: no match for ‘operator=’ in ‘ptr_map_A.boost::ptr_map<unsigned int, A, std::less<unsigned int>, boost::heap_clone_allocator, std::allocator<std::pair<const unsigned int, void*> > >::<anonymous>.boost::ptr_map_adapter<A, std::map<unsigned int, void*, std::less<unsigned int>, std::allocator<std::pair<const unsigned int, void*> > >, boost::heap_clone_allocator>::<anonymous>.boost::ptr_container_detail::ptr_map_adapter_base<T, VoidPtrMap, CloneAllocator>::operator[] [with T = A, VoidPtrMap = std::map<unsigned int, void*, std::less<unsigned int>, std::allocator<std::pair<const unsigned int, void*> > >, CloneAllocator = boost::heap_clone_allocator](((const unsigned int&)((const unsigned int*)(&0u)))) = (((A*)operator new(8u)), (<anonymous>->A::A(0.0), <anonymous>))’ ../header.h:4: note: candidates are: A& A::operator=(const A&) /usr/local/boost_1_34_1/boost/ptr_container/ptr_map_adapter.hpp: In member function ‘typename boost::ptr_container_detail::associative_ptr_container<boost::ptr_container_detail::map_config<T, VoidPtrMap>, CloneAllocator>::reference boost::ptr_container_detail::ptr_map_adapter_base<T, VoidPtrMap, CloneAllocator>::insert_lookup(const typename boost::ptr_container_detail::associative_ptr_container<boost::ptr_container_detail::map_config<T, VoidPtrMap>, CloneAllocator>::key_type&) [with T = A, VoidPtrMap = std::map<unsigned int, void*, std::less<unsigned int>, std::allocator<std::pair<const unsigned int, void*> > >, CloneAllocator = boost::heap_clone_allocator]’: /usr/local/boost_1_34_1/boost/ptr_container/ptr_map_adapter.hpp:268: instantiated from ‘typename boost::ptr_container_detail::associative_ptr_container<boost::ptr_container_detail::map_config<T, VoidPtrMap>, CloneAllocator>::reference boost::ptr_container_detail::ptr_map_adapter_base<T, VoidPtrMap, CloneAllocator>::operator[](const typename boost::ptr_container_detail::associative_ptr_container<boost::ptr_container_detail::map_config<T, VoidPtrMap>, CloneAllocator>::key_type&) [with T = A, VoidPtrMap = std::map<unsigned int, void*, std::less<unsigned int>, std::allocator<std::pair<const unsigned int, void*> > >, CloneAllocator = boost::heap_clone_allocator]’ ../main.cpp:22: instantiated from here /usr/local/boost_1_34_1/boost/ptr_container/ptr_map_adapter.hpp:168: error: no matching function for call to ‘A::A()’ ../header.h:6: note: candidates are: A::A(double) ../header.h:4: note: A::A(const A&) make: *** [main.o] Error 1 make: Target `all' not remade because of errors. Build complete for project testing_map

2 1

[program_options] Short name strategy
by Larry 14 Aug '07

14 Aug '07

I didn't see anythiing in the doc but is there some compelling reason why short names for options was limited to a single character? The code fails an assert if the short name is more than one character. It just seems like an unnecessary limitation. Larry

2 1

Meaning of a library suffix
by Philippe Mondon 14 Aug '07

14 Aug '07

Hi, Can anyone tell me what means the library suffix : *sgd-*.lib My code on windows wants to link with this library and I don't understand why. Thanks, Regards, Philippe Mondon Equipe PAC/Architecture DIMC Calyon Ce message et ses pièces jointes (le "message") est destiné à l'usage exclusif de son destinataire. Si vous recevez ce message par erreur, merci d'en aviser immédiatement l'expéditeur et de le détruire ensuite. Le présent message pouvant être altéré à notre insu, CALYON Crédit Agricole CIB ne peut pas être engagé par son contenu. Tous droits réservés. This message and/or any attachments (the "message") is intended for the sole use of its addressee. If you are not the addressee, please immediately notify the sender and then destroy the message. As this message and/or any attachments may have been altered without our knowledge, its content is not legally binding on CALYON Crédit Agricole CIB. All rights reserved.

2 2

[program_options] how to link to the release version of static library
by 顾铭秋 14 Aug '07

14 Aug '07

Hi, I'm using Boost 1.34.1 with MS VC8. Release version of my project will link to the debug version of static library (libboost_program_options-vc80-mt-sgd-1_34_1.lib). This will cause some link error (symbol redefinition in debug and release version of system library). How can I link to the release version of the library(libboost_program_options-vc80-mt-s-1_34_1.lib)? Thanks! MQ Gu

1 0

Re: [Boost-users] [tests] Signals not well covered in unit tests (incontrast to exceptions)?
by Gennadiy Rozental 14 Aug '07

14 Aug '07

> "Jens Seidel" <jensseidel(a)users.sf.net> wrote in message > news:20070726151640.GA19199@imkf-pc073.imkf.tu-freiberg.de... > Hi, > > I have the following problem with a C++ project on Linux using the > Boost.test framework: Can you write simple example that show the problem? Gennadiy

2 2

boost test documentation update.
by Yann Golanski 14 Aug '07

14 Aug '07

Is there an ETA to the Boost test documentation update? At the moment, the documentation is rather poor which is a shame since the library is good. -- yann(a)kierun.org -= H+ =- www.kierun.org PGP: 009D 7287 C4A7 FD4F 1680 06E4 F751 7006 9DE2 6318

2 1

Spirit - Cannot get my actors straight
by Anders Dalvander 14 Aug '07

14 Aug '07

Hi, I'm trying to create a parser that shall create a number of derived classes based on the input, put it in a shared_ptr<Base> and push_back to a vector. Example: "Alpha" => vec.push_back(shared_ptr<Base>(new Alpha())) "Beta[1]" => vec.push_back(shared_ptr<Base>(new Beta(1))) "Gamma[2-3]" => vec.push_back(shared_ptr<Base>(new Gamma(2, 3))) "Gamma[4-End]" => vec.push_back(shared_ptr<Base>(new Gamma(4))) I've defined the actor as [push_back_a(self.vec, BasePtr(new Alpha()))], but that obviously doesn't work as BasePtr(new Alpha()) creates a temporary shared_ptr that will be destroyed by the end of the statement. How can I delay the creation of the shared_ptr, and how can I delay the new statement? Using Boost 1.34.1, MSVC++ 2005. Thanks, Anders Dalvander #include <vector> #include <boost/optional.hpp> #include <boost/shared_ptr.hpp> #include <boost/spirit.hpp> #include <boost/spirit/actor/push_back_actor.hpp> #include <boost/spirit/phoenix.hpp> using namespace boost::spirit; using namespace phoenix; class Base { public: virtual ~Base() = 0 {} }; typedef boost::shared_ptr<Base> BasePtr; class Alpha : public Base { public: Alpha() {} virtual ~Alpha() {} }; class Beta : public Base { public: explicit Beta(int var) : var(var) {} virtual ~Beta() {} private: int var; }; class Gamma : public Base { public: explicit Gamma(int var1) : var1(var1), var2() {} Gamma(int var1, int var2) : var1(var1), var2(var2) {} virtual ~Gamma() {} private: int var1; boost::optional<int> var2; }; struct my_grammar : grammar<my_grammar> { template <typename ScannerT> struct definition { typedef rule<ScannerT> rule_t; explicit definition(const my_grammar& self) { my_rule = str_p("Alpha")[push_back_a(self.vec, BasePtr(new Alpha()))] | ("Beta[" >> int_p[var(var1) = arg1] >> "]")[push_back_a(self.vec, BasePtr(new Beta(var1)))] | ("Gamma[" >> int_p[var(var1) = arg1] >> "-" >> int_p[var(var2) = arg1] >> "]")[push_back_a(self.vec, BasePtr(new Gamma(var1)))] | ("Gamma[" >> int_p[var(var1) = arg1] >> "-End]")[push_back_a(self.vec, BasePtr(new Gamma(var1)))] ; } int var1; int var2; rule_t my_rule; const rule_t& start() const { return my_rule; } }; my_grammar(std::vector<BasePtr>& vec) : vec(vec) { } std::vector<BasePtr>& vec; }; int main() { std::vector<BasePtr> vec; my_grammar g(vec); parse("Alpha", g); parse("Beta[1]", g); parse("Gamma[2-3]", g); parse("Gamma[4-End]", g); }

2 1

[statechart] orthogonal states in state_machine?
by Chris Paulse 13 Aug '07

13 Aug '07

I would like to create a state_machine class that contains some context information that can be written by orthogonal<0> and read by orthogonal<1>. Graphically: _______________ | State Machine | |_______________|______________ | | | StateA1 <------> StateA2 | | - - - - - - - - - - - - - - | | StateB1 <------> StateB2 | |_______________________________| I declare using struct StateA1, StateB1; struct MyStateMachine : sc::state_machine< MyStateMachine, mpl::list<StateA1, StateB1> > {}; struct StateA1 : sc::simple_state<StateA1, MyStateMachine::orthogonal<0> > {}; but get a compile error on line 2 as "orthogonal not a member of MyStateMachine". Do I need to declare one state in MyStateMachine, and make the mpl::list a second template argument to it in order to get what I want? Thanks in advance, Chris

2 1

mpl question: object hierarchies
by Gross, Steve 13 Aug '07

13 Aug '07

Is there a way to use the mpl to determine if an object can be converted to some parent / child class? That is, if A derives from B, can I say something like "mpl::is_convertible_to<A, B>::value" ? Thanks, --Steve

2 1

[ScopeExit/Typeof] Can't build simple test in debug mode (MSVC 7.1 and 8.0)
by Christian Larsen 13 Aug '07

13 Aug '07

Hi, I'm trying build a very simple test program using ScopeExit (just downloaded from the link in the review notice: http://boost-consulting.com/vault/index.php?action=downloadfile&filename=sco pe_exit-0.04.tar.gz&directory=& ). I'm using a brand new download of Boost 1.34.1 with it. The following code builds and runs fine in release mode in both VC7.1 and 8.0, but fails to build in debug mode in both versions. I also tried specifying the BOOST_TYPEOF_COMPLIANT in MSVC7.1 debug but to no avail - I just get some other errors. I couldn't find any indication of what would cause this difference between debug/release builds. I tried disabling optimizations in release mode to check whether this would cause release mode to fail, too, but it didn't. Any help would be appreciated. Best regards, Christian Larsen Code: #include <iostream> #include <boost/scope_exit.hpp> int main(int argc, char* argv[]) { bool commit = false; BOOST_SCOPE_EXIT( (commit) ) { if( !commit ) std::cerr << "Not committed!\n"; } BOOST_SCOPE_EXIT_END //commit = true; return 0; } Building debug mode MSVC 7.1: Compiling... ScopeExitTest.cpp using native typeof d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2513: 'boost::type_of::msvc_typeid_wrapper<ID>::type' : no variable declared before '=' with [ ID=5 ] d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2039: 'type' : is not a member of 'operator``global namespace''' d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2440: 'type cast' : cannot convert from 'long' to 'boost::type_of::msvc_typeid_wrapper<ID>::type' with [ ID=5 ] No constructor could take the source type, or constructor overload resolution was ambiguous d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2146: syntax error : missing ';' before identifier 'type' d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2065: 'type' : undeclared identifier d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2146: syntax error : missing ';' before identifier 'commit_boost_scope_exit_typeof' [...] Building debug mode MSVC 7.1 (with BOOST_TYPEOF_COMPLIANT): Compiling... ScopeExitTest.cpp using typeof emulation d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2440: 'type cast' : cannot convert from 'long' to 'main::commit_boost_scope_exit_nested_typeof' Source or target has incomplete type d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2143: syntax error : missing ';' before ':' d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2143: syntax error : missing ';' before ':' d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2143: syntax error : missing ';' before '{' d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2039: 'type' : is not a member of 'operator``global namespace''' d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2513: 'int' : no variable declared before '=' d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2146: syntax error : missing ';' before identifier 'type' d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2065: 'type' : undeclared identifier d:\Development\Misc\ScopeExitTest\ScopeExitTest.cpp(8) : error C2146: syntax error : missing ';' before identifier 'commit_boost_scope_exit_typeof' [...] Building debug mode MSVC 8.0: Compiling... ScopeExitTest.cpp using typeof emulation d:\development\misc\scopeexittest\scopeexittest.cpp(8) : error C2440: '<function-style-cast>' : cannot convert from 'long' to 'main::commit_boost_scope_exit_nested_typeof' Source or target has incomplete type d:\development\misc\scopeexittest\scopeexittest.cpp(8) : error C2143: syntax error : missing ';' before ':' d:\development\misc\scopeexittest\scopeexittest.cpp(8) : error C2143: syntax error : missing ';' before ':' d:\development\misc\scopeexittest\scopeexittest.cpp(8) : error C2143: syntax error : missing ';' before '{' d:\development\misc\scopeexittest\scopeexittest.cpp(8) : error C2039: 'type' : is not a member of '`global namespace'' d:\development\misc\scopeexittest\scopeexittest.cpp(8) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int d:\development\misc\scopeexittest\scopeexittest.cpp(8) : error C2513: 'int' : no variable declared before '=' d:\development\misc\scopeexittest\scopeexittest.cpp(8) : error C2146: syntax error : missing ';' before identifier 'type' [...]

1 0

Boost Serialization with a dynamically loaded shared library
by Jeshua Bratman 13 Aug '07

13 Aug '07

I've been trying to get Boost serialization working for dynamically loaded shared libraries. Here's my basic structure simplified: 1. base.hpp - includes an abstract base class called base 2. derived.hpp - includes a derived class from base. includes base.hpp. 3. derived.cpp - includes code for derived class and for dynamically loading it 4. main.cpp - includes base.hpp but NOT derived.hpp. dynamically loads instantiates a base * which points to a derived object from derived.so Now in main I want to be able to serialize my pointer to the loaded derived class: base *obj = create_func(); //obj now points to a derived object obj->test(); //when test is run it correctly outputs the message from derived.cpp const base *to_serialize = obj; //it seems to want a const pointer in order to serialize std::ofstream ofs("filename"); boost::archive::text_oarchive oa(ofs); oa << (*to_serialize); main.cpp compiles fine, but when it gets to the last line there, the serialize method in base is called, not the one in derived. I read http://www.boost.org/libs/serialization/doc/serialization.html#derivedpoint… http://www.boost.org/libs/serialization/doc/serialization.html#derivedpoint… but it doesn't seem to address this problem (unless I missed something?). I can't use the BOOST_CLASS_EXPORT_GUID(derived, "derived") macro discussed on that page because main does not know what a derived object is (this is the whole point of having this plugin system). Is there any way I can make boost serialization correctly serialize the derived class from the base pointer when the derived object is known only to a dynamically loaded library? Thank you for your help, Jeshua Bratman -- View this message in context: http://www.nabble.com/Boost-Serialization-with-a-dynamically-loaded-shared-… Sent from the Boost - Users mailing list archive at Nabble.com.

3 11

Re: [Boost-users] Regular expression min match length
by Raffaele Romito 13 Aug '07

13 Aug '07

Thanks for the reply John, I'll try to expose my "use case" with the hope this feature will be available in the future... I'm developing a system that detects TCP streams with a pattern matching, here is the pseudo code (in a simplified form) of the function I'd link to extend: protocol_stream decodeStream(tcp_stream) { foreach(registered protocol in the system) { required_size_to_match = calc_min_regex_len(current_protocol.regex); if(tcp_stream.buffer_size <= required_size_to_match) check if tcp_stream.buffer matches else try to read from tcp_stream if data is available until <required_size_to_match> and check again if matches } } Hope u can help since you have "an almost pathological interest in anything that can't be done" :) Thanks again _________________________________________________________________ C'è una nuova amica su Messenger… E' Doretta, vieni a conoscerla! http://www.doretta82.it/banner/index.html

3 2

ScopeExit Review Begins Today
by Jody Hagins 13 Aug '07

13 Aug '07

The review period for Scope Exit Time Series, submitted by Alexander Nasonov, runs from Monday, August 13 until Wednesday, August 22. >From the documentation: Nowadays, every C++ developer is familiar with RAII technique. It binds resource acquisition and release to initialization and destruction of a variable that holds the resource. But there are times when writing a special class for such variable is not worth the effort. This is when ScopeExit macro comes into play. You put resource acquisition directly in your code and next to it you write a code that releases the resource. Note that ScopeExit uses PP macros and relies on Boost.Typeof. The latest version can is here: http://boost-consulting.com/vault/index.php?action=downloadfile&filename=sc… It's available also at http://tinyurl.com/2z6qg2 Online documentation is here: http://194.6.223.221/~nasonov/scope_exit-0.04/libs/scope_exit/doc/html/inde… >From the review guidelines here: http://boost.org/more/formal_review_process.htm ... Boost mailing list members are encouraged to submit Formal Review comments: * Publicly on the mailing list. * Privately to the Review Manager. Private comments to a library submitter may be helpful to her or him, but won't help the Review Manager reach a decision, so the other forms are preferred. What to include in Review Comments Your comments may be brief or lengthy, but basically the Review Manager needs your evaluation of the library. If you identify problems along the way, please note if they are minor, serious, or showstoppers. Here are some questions you might want to answer in your review: * What is your evaluation of the design? * What is your evaluation of the implementation? * What is your evaluation of the documentation? * What is your evaluation of the potential usefulness of the library? * Did you try to use the library? With what compiler? Did you have any problems? * How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? * Are you knowledgeable about the problem domain? And finally, every review should answer this question: * Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Thanks in advance to every for your participation in this review.

1 0

[Lambda] Question about calling a member function inside a lambda construct
by Hendrik Belitz 13 Aug '07

13 Aug '07

Hello, I'm rather stucked in using lambda expressions for a presumably simple task. Suppose I have objects with a member function bool is_empty() const; stored in a vector: I want to count the number of objects for which their member functions returns false, which is simple, but not elegant to achieve by size_t sum = 0; for( Foo::const_iterator it = vec.begin(); it != vec.end(); ++it ) if ( it->is_empty() == false ) sum++; I want to exchange this for a lambda expression, and came up with the following after some thinking. for_each( begin(), end(), if_then( !(_1 ->* &GridCell::is_empty)(), var(sum)++ ) ); This is still wrong and leads to two error messages: error C2784: 'const boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lamb da::logical_action<Action>,boost::tuples::tuple<boost::lambda::lambda_functo r<T>>>> boost::lambda::operator !(const boost::lambda::lambda_functor<T> &)' : could not deduce template argument for 'const boost::lambda::lambda_functor<T> &' from 'boost::tuples::null_type' error C2675: unary '!' : 'boost::tuples::null_type' does not define this operator or a conversion to a type acceptable to the predefined operator Could anyone tell how to get this working? Regards Hendrik -- Hendrik Belitz ISD Software und Systeme GmbH Hauert 4 D - 44227 Dortmund Germany Fon: +49 (0)231/97 93-0 Fax: +49 (0)231/97 93-101 Mail: <mailto:hBelitz@isdcad.de> hBelitz(a)isdcad.de Internet: <http://www.isdcad.de/> www.isdcad.de Geschäftsführung: Günter Flassig (Vors.), Dr. Jörg Ruhwedel Sitz Dortmund, Amtsgericht Dortmund HRB 4601

2 2

Fwd: Resizing a symmetric matrix
by Tinne De Laet 13 Aug '07

13 Aug '07

Hi, While using the most recent version of Boost (boost_1_34_1) I noticed some problems when resizing a symmetric matrix. I included a test program to illustrate the problems. (Recent SVN snapshots and boost 1.33 have the same problem) When executing I get the following error caused by resizing the symmetric matrix with the preserve option set to true: Resize ml to bigger size Check failed in file /home/fiep/sources/boost_1_34_1/boost/numeric/ublas/storage.hpp at line 196: i < size_ terminate called after throwing an instance of 'boost::numeric::ublas::bad_index' what(): bad index Aborted (core dumped) Note that are no problems when resizing normal matrices nor resizing symmetric matrices when the preserve option is set to false. When stepping into the program, it seems that something goes wrong with the indexing of the symmetric matrix. I suspect that problems are caused by the use of the matrix_resize_preserver routine which is called in case the preserve option is set to true. I think this routine is designed for normal matrices only and expects a matrix which is completely filled as opposed to a symmetric matrix in which only one triangle is filled. Do I use the library in a wrong way or might this be a BUG? Kind regards, Tinne De Laet _______________________________________ Tinne De Laet Department of Mechanical Engineering - PMA Katholieke Universiteit Leuven Celestijnenlaan 300B - bus 2420 3001 Heverlee Tel: +32 (0)16 32 25 33 http://people.mech.kuleuven.be/~tdelaet/ _______________________________________ Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm

1 0

(no subject)
by Trigve Siver 13 Aug '07

13 Aug '07

Hi all, On gtkmm mailing was posted mail about using boost in gtkmm... Could someone post some info about API, ABI stability of boost? thanks Trigve mail from gtkmm list: //---------------------- Boost is not a stable API. If it ever declares API and ABI stability then we could use it. Using boost now would break already-installed applications and break compilation of applications when boost is upgraded. When parts of the Boost API become part of the official C++ standard then we would use that API where appropriate. For instance, we hope to port to a standard C++ signals API in the future. That API was largely based on libsigc++ anyway. On Mon, 2007-08-13 at 12:27 +0800, manphiz wrote: > Hi gtkmm developers: > > I'm a new-comer to gtkmm, who found gtkmm a ideal GUI toolkit based on > the philosophy of standard C++, which exactly matches my anticipation. > > On the other hand, glibmm/gtkmm is virtually a wrapper of gtk+ stuff, > which also has to reflect the interface of the original stuff. While > Boost is a well-known C++ library collection which has many overlaps in > many aspects with glibmm, such as smart pointer, thread support. > Recently, a feature request for weak pointer in glibmm and the recent > compose api proposed by Daniel Elstner are resemblances as > boost::weak_ptr and boost::format, which provide similar functionalities. > > Here's the question: whether to reuse Boost or to reinvent all needed > functionailities in glibmm? Though there seems a reluctance to use Boost > which already results in many reinvention in glibmm, I don't think it is > a good idea. Boost is becoming more and more widely used within C++ > community. To reinvent is simply a waste of resource, and may even > result in different design and implementation which will definitely > compromise the interoperability between Boost and gtkmm. With the fact > of gtk+ binding, I believe the existence of libsigc++ indicates > glibmm/gtkmm is not a zealot to become a strict binding with gtk+ stuff. > While Boost is indeed a much heavier library than libsigc++, it still > merits reusing in gtkmm. Moreover, many Boost stuff are going to become > part of C++0x, which means smart_ptr, threads, regex, etc. will become a > part of the language itself, which in turn will loose the need of some > stuff currently in glibmm. Due to the binding reality, it is impossible > to do everything in Boost, but some of them can benefit a lot. > > I wonder if such a migration to Boost is possible? A reimplementation > with gtkmm may be infeasible since it will destroy the binary > compatibility. Changing glibmm stuff to be a binding of Boost without > changing its interfaces sounds viable, which will ultimately save gtkmm > a lot of work in the long run. What do you think? > > _______________________________________________ > gtkmm-list mailing list > gtkmm-list(a)gnome.org > http://mail.gnome.org/mailman/listinfo/gtkmm-list -- murrayc(a)murrayc.com www.murrayc.com www.openismus.com _______________________________________________ gtkmm-list mailing list gtkmm-list(a)gnome.org http://mail.gnome.org/mailman/listinfo/gtkmm-list //---------------------- ____________________________________________________________________________________ Boardwalk for $500? In 2007? Ha! Play Monopoly Here and Now (it's updated for today's economy) at Yahoo! Games. http://get.games.yahoo.com/proddesc?gamekey=monopolyherenow

1 0

Re: [Boost-users] boost::iostreams::gzip_compressor and multiplefiles
by John Reynolds 13 Aug '07

13 Aug '07

Yu can try zipios http://sourceforge.net/projects/zipios John Reynolds Aircraft Management Technologies Limited Registered in Ireland, No.337561 Registered office: 1 The Green, Malahide, Co.Dublin, Ireland Tel: + 353 1 8061000 Fax:+ 353 1 8061025 -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Jens Seidel Sent: 10 August 2007 13:22 To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] boost::iostreams::gzip_compressor and multiplefiles On Thu, Aug 09, 2007 at 11:38:58AM -0400, François Duranleau wrote: > On Thu, 9 Aug 2007, Robert Caldecott wrote: > >However, I want to create a single gzip file that contains multiple > >compressed > >files, each with a different filename. Does anyone know how to achieve > >this? > > I guess that when you uncompress the file (e.g. with gunzip), you want to > get all those named files in, well, different files? As far as I know, the > gzip format doesn't allow that (I could be wrong), hence the gzip'ed tar Right, it doesn't allow it and this is fine. Why should gzip allow archiving multiple files? It is a compressing program, not more. It's again the usual (and fine) Unix philosophy: one program for a simple task, combine/pipe multiple such simple programs to get more complex tasks done. This way you can also compress via gzip other archive formats, do not increase the code base of gzip and make compressing alone usable for other programs as well (which do not require tar). I would wish such a solution would be used on the proprietary systems which use ZIP as default archiver as well ... Jens _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

1 0

Problem message Boost Code Blocks
by question boost 13 Aug '07

13 Aug '07

Hi, using Code Blocks i got the folowing message: ld.exe "Cannot find -lboost_filesystem-mgw-mt-s-l_33_l". So I did :cd /jam source location/ then I execute build.bat Then, i put the following variables: path=C:\Program Files\CodeBlocks\bin BOOST_BUILD_PATH=C:\Documents and Settings\Administrateur\Bureau\boost_1_33_1\boost_1_33_1\tools\build\v2 BOOST_ROOT=C:\Documents and Settings\src\boost But i get the message again. What is the right thing to do in order not to get the message any more? Thank you for your answer because nobody has ever answered this question yet. Thank You _________________________________________________________________ Le blog Messenger de Michel, candidat de la Nouvelle Star : analyse, news, coulisses… A découvrir ! http://michel-nouvelle-star2007.spaces.live.com/

3 2

Regular expression min match length
by Raffaele Romito 13 Aug '07

13 Aug '07

Hi, I need to calculate, given a regular expression, the min length for a match. For example if I have as regexp ^HTTP.*, 4 is the min length required for a match. Is it possible? Plz help... Bye _________________________________________________________________ C'è una nuova amica su Messenger… E' Doretta, vieni a conoscerla! http://www.doretta82.it/banner/index.html

3 2

Message Boost Code Blocks
by question boost 13 Aug '07

13 Aug '07

Hi, using Code Blocks i got the folowing message: ld.exe "Cannot find -lboost_filesystem-mgw-mt-s-l_33_l". So I did :cd /jam source location/then build.bat Then, i put the following variables: path=C:\Program Files\CodeBlocks\bin BOOST_BUILD_PATH=C:\Documents and Settings\Administrateur\Bureau\boost_1_33_1\boost_1_33_1\tools\build\v2 BOOST_ROOT=C:\Documents and Settings\src\boost It is not the right things to do => i get the message again. My question is: What are the right things to do in order not to get the message any more? Thank You _________________________________________________________________ Besoin d'un e-mail ? Créez gratuitement un compte Windows Live Hotmail et gagnez du temps avec l'interface à la Outlook ! http://www.windowslive.fr/hotmail/default.asp

1 0

complexity of boost::num_vertices boost::num_edges
by Heiko Bauke 12 Aug '07

12 Aug '07

Hi, I wonder what is the time complexity of boost::num_vertices and boost::num_edges? Are these constant time operations? I could not find an answer to this question in BGL documentation. Regards, Heiko -- -- Never ascribe to malice, that which can -- be explained by incompetence. (Napoleon) -- Cluster Computing @ http://www.clustercomputing.de -- Heiko Bauke @ http://www.physics.ox.ac.uk/users/bauke

2 1

Re: [Boost-users] cross compiling boost for ARM
by Hughes, James 12 Aug '07

12 Aug '07

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of remi > Sent: 05 January 2007 14:44 > To: boost-users(a)lists.boost.org > Subject: [Boost-users] cross compiling boost for ARM > > > hi! > > I want to cross compile boost for an ARM processor. > For a pxa 270. but when i try to cross compile boost with > arm-linux-g++ , it dosen't work ... a proble with jam... > > everyone can help me? > > Thank you > > BEST REGARDS > > Rémi bjam "-sGCC_ROOT_DIRECTORY=/opt/montavista/mobilinux/devkit/arm/iwmmxt_le" "-sGCC=iwmmxt_le-gcc" "-sGXX=iwmmxt_le-g++" <location for libs> Obviously you would need to change the location namd names of the compile tools to whatever you are using. James This message (including any attachments) contains confidential and/or proprietary information intended only for the addressee. Any unauthorized disclosure, copying, distribution or reliance on the contents of this information is strictly prohibited and may constitute a violation of law. If you are not the intended recipient, please notify the sender immediately by responding to this e-mail, and delete the message from your system. If you have any questions about this e-mail please notify the sender immediately.

3 3

shared_ptr, pimpl, reference semantics, and const correctness
by Braddock Gaskill 11 Aug '07

11 Aug '07

I am continuing work on a futures library for boost. future objects (as currently considered by the C++ standards committee, in particular Peter Dimov's proposal) have reference semantics, like many pimpl types. I have some burning questions about const correctness. Hypothetical reference-semantic example: future f1; future f2 = f1; //f2 refers to the same underlying object as f1 f2.set(42); //do something assert(f1.get() == 42); // see, same underlying object This is roughly equivalent to: boost::shared_ptr<future_impl> f1; boost::shared_ptr<future_impl> f2 = f1; A std::vector<T>::iterator is an example of another type with reference semantics. So, say I have a simple future class: class future_impl { public: bool get() const {return value_;} void set(bool value) {value_ = value;} private: bool value_; }; class future { //not really a future, just example public: future() : impl_(new future_impl) {} future(const future &other) : impl_(other.impl_) {} bool get() const {return impl_->get();} // Set may not be const, but it does NOT really modify this class void set(bool value) {impl_->set(value);} private: boost::shared_ptr<future_impl> impl_; }; I have made the future::set() method non-const, but it does NOT really modify the underlying future class, only the future_impl class it refers to. This makes life very difficult when it comes to passing futures by reference: // alternative #1 - pass const future & void f1(const future &f) { bool v = f.get(); // no problem, get() is const f.set(!v); // cannot do this, set() is not const // BUT I can bypass the const-ness trivially, so it is pointless future f2(f); f2.set(!v); } // alternative #2 - pass future & // with #2, I can't do simple things like this: // f2(future(f)); //ERROR: non-const reference from a temporary - irritating void f2(future &f) { bool v = f.get(); // no problem, get() is const f.set(!v); } // alternative #3 - pass by value // Constructing shared_ptr's is VERY inefficient void f3(future f) { bool v = f.get(); // no problem, get() is const f.set(!v); // cannot do this, set() is not const } // alternative #4 - const_future base class with the subset of const methods? // kinda like a const_iterator? seems klunky. class const_future {bool get() const;}; class future : public const_future {void set(bool);} Does anyone have any advice or ideas? Oh, and then there is a possible need for something like a weak_ptr<future_impl>, like a weak_future class? And then a const_weak_future? I don't want to think about it... Thanks, Braddock Gaskill

3 4

Installer for Boost 1.34.1
by Rusty Jones 11 Aug '07

11 Aug '07

Hi, Does anyone know if boost consulting is going to provide an installer for 1.34.1 and if so what time frame? Cheers, Rusty

2 2

BOOST libraries still not part of BOOST dist
by dhruva 11 Aug '07

11 Aug '07

Hi, I am wondering if there is a list of all BOOST libraries which are under under review or accepted for future inclusions. Is "VAULT" the right place to look for such libraries? A list with a short writeup would be very useful. I know the interprocess and asio library existance and hence can google around to find their download locations. There may be many other libraries (I stumbled upon Channel and join) which is not listed in the BOOST site (in a comprehensive, single page manner). -dky -- Dhruva Krishnamurthy Contents reflect my personal views only!

3 2

Serialization of infinite float
by Arnstein Ressem 11 Aug '07

11 Aug '07

Hi, I have run into a problem with the boost xml serialization of overflowing floats. On Linux these are being serialized as 'inf' into the xml files, but when reading the float back in it results in stream errors. I have searched the archives to find an answer to this, but without luck. The small program below has been compiled and run on 32-bit and 64-bit Linux (RedHat Enterprise Linux 4) with boost 1.33.1 and 1.34.1. In every case it results in a stream error and the float can not be read back in from the xml file. Does anyone know if this is supposed to work ? #include <fstream> #include <boost/archive/xml_iarchive.hpp> #include <boost/archive/xml_oarchive.hpp> int main() { const char fname[] = "float.xml"; float f = 1.0e+20*1.0e+20; { std::ofstream ofs(fname); assert(ofs.good()); boost::archive::xml_oarchive oa(ofs); oa << BOOST_SERIALIZATION_NVP(f); } { std::ifstream ifs(fname); assert(ifs.good()); boost::archive::xml_iarchive ia(ifs); ia >> BOOST_SERIALIZATION_NVP(f); } return 0; } Best regards, Arnstein Ressem

4 3

Boost Math Toolkit: Compare simulation data
by NFarnsworth＠web.de 11 Aug '07

11 Aug '07

Hallo, I want to use the test function from the boost math toolkit library to compare simulation results of mechantronic systems with a reference solution. The test reads the reference solution from a file, and after the simulation the test compares the file data with the data from a double array. But if a value of a function is close to zero, I will get a gross relative error. Do you have any suggestion to solve this problem? Thanks for your help in advance Best regards Niklas _______________________________________________________________________ Jetzt neu! Schützen Sie Ihren PC mit McAfee und WEB.DE. 3 Monate kostenlos testen. http://www.pc-sicherheit.web.de/startseite/?mc=022220

2 1

What happened to boost::thread priority?
by Graham Reitz 10 Aug '07

10 Aug '07

I was looking through the list archives and its looks like the a feature to set the thread priority fizzled out around 2003ish. Did this get tabled? This is really a curiosity question. Thanks, Graham

1 0

[boost.python] can not export a union in VC2005sp1
by qiaozhiqiang＠datangmobile.cn 10 Aug '07

10 Aug '07

// Visual V++ 2005(8.0) sp1, boost 1.34.0 // union not is_class. // because there is BOOST_STATIC_ASSERT(is_class<T>::value) in make_instance_impl // can not export union. eg, class_<union my_u> // can not return_internal_reference<> when T not is_class, eg, return char*, char&, union u& // how to write return_internal_pointer: char* get(); // how to return_value_policy<return_by_value> work: char* get() // def_readwrite(union): default get() return by value ? // is_class<T> ? T& : T get() ?? // delete BOOST_STATIC_ASSERT(is_class<T>::value); of make_instance_impl, then compile OK, and work not all OK boost/python/object/make_instance.hpp template <class T, class Holder, class Derived> struct make_instance_impl { typedef objects::instance<Holder> instance_t; template <class Arg> static inline PyObject* execute(Arg& x) { // must is_class ?? to BOOST_STATIC_ASSERT(is_class<T>::value || is_union<T>::value)?? BOOST_STATIC_ASSERT(is_class<T>::value); /////////////////////////////// #include <boost/python.hpp> using namespace boost::python; union my_u { int a; char b; char& get_ref() { return b; } char* get_ptr() { return *b; } } struct my_s { my_u u; my_u& get_ref() { return u; } my_u* get_ptr() { return &u; } }; void my_module() { //1. compile ERROR: my_u not is_class, my_u is_union, I modify one line in make_instance.hpp // BOOST_STATIC_ASSERT(is_class<T>::value) to //BOOST_STATIC_ASSERT(is_class<T>::value || is_union<T>::value) // and the def_readwrite a, b work OK. // and work OK, why not export an union? class_<my_u > u_class("my_u", init< >()); u_class.def_readwrite("a", &my_u::a); u_class.def_readwrite("b", &my_u::b); //2. compile ERROR: char not is_class, delete BOOST_STATIC_ASSERT(is_class<T>::value), but run error u_class.def("get_ref", &my_u::get_ref, return_internal_reference< >()); //3. compile ERROR: char not is_class, delete BOOST_STATIC_ASSERT(is_class<T>::value), but run error, how to return_internal_reference a char? Use def_readwrite？ u_class.def("get_ptr", &my_u::get_ptr, return_internal_reference< >()); //4. compile OK, but run ERROR, I need it return a char .def("get_value", &my_u::get_ptr, return_value_policy<return_by_value>()); //5. compile ERROR, char* is not a reference, I need but have no copy_non_const_pointer, how to write copy_non_const_pointer? u_class.def("get_copy", &my_u::get_ptr, return_value_policy<copy_non_const_reference>()); class_<my_s > s_class("my_s", init< >()); //6. compile OK, buy run ERROR: // s = my_s() // s.u.a = 100 // print s.u.a // but output s.u.a != 100 !!! // s.u.a = 100 is s.get_u().set_a(100) and get_u() not return u(is_union) by ref ? s_class.def_readwrite("u", &my_s::u); // 7. compile ERROR: my_u not is_class, is_union, modify BOOST_STATIC_ASSERT(is_class<T>::value) to // BOOST_STATIC_ASSERT(is_class<T>::value || is_union<T>::value) s_class.def("get_ptr", &my_s::get_ptr, return_internal_reference<>()); s_class.def("get_ref", &my_s::get_ref, return_value_policy<return_by_value>());//compile ok } Best 　Regards ! Qiao Zhi Qiang

2 1

Process for adding code to boost
by Hughes, James 10 Aug '07

10 Aug '07

Hello all, I was interested in knowing how to go about presenting new code for addition to boost. I'm not talking about a new library, but extensions to existing ones. For example, I have written some code to allow serialisation of the boost::filesystem::path class (not particularly exciting or complicated, but may be useful to someone), and would like to pass it on. James This message (including any attachments) contains confidential and/or proprietary information intended only for the addressee. Any unauthorized disclosure, copying, distribution or reliance on the contents of this information is strictly prohibited and may constitute a violation of law. If you are not the intended recipient, please notify the sender immediately by responding to this e-mail, and delete the message from your system. If you have any questions about this e-mail please notify the sender immediately.

8 14

unique sorted vector
by Michael Marcin 10 Aug '07

10 Aug '07

I have a need for a low memory set. Essentially I want an always sorted unique vector. Is such a wrapper around vector and/or deque available in Boost? Thanks, Michael Marcin

1 0

Avoid thread locking with boost::condition
by Sam Lievesley 10 Aug '07

10 Aug '07

Hi, I am trying to avoid thread locking problems when waiting using a boost::condition pseudo code: Main thread -- Start a worker thread -- boost::mutex::scoped_lock lock(m_Mutex); m_Condition.notify_one(); Worker thread boost::mutex::scoped_lock lock(m_Mutex); while (IsAlive()) { // do some work m_Condition.wait(lock); } As we can't predict which thread gets the mutex lock first lets assume that its the main thread. If this happens then m_Condition.wait will wait indefinitely as notify was called before wait. The only reliable way (that I can see) to prevent this is to never use wait, use a timed_wait instead and a loop. Why isn't the notification signal queued in the boost::condition object? Then the order of wait / notification would not be important. thanks Sam

2 1

Visual Studio 2005 ptr_list visualizer?
by Michael Marcin 10 Aug '07

10 Aug '07

Hello I've seen Visual Studio 2005 visualizers for various boost containers on here before. Has anyone written one for ptr_list that they can share? Thanks, Michael Marcin

5 15

Problem with boost::bind and boost::lambda::bind
by Stefano Peluchetti 10 Aug '07

10 Aug '07

I'm a newbie to the boost library so I need some help with the following problem: Take the following code: class EaSde // Abstract class. { ... public: inline virtual double unitDiffusionInverseMap( double x ) const = 0; inline virtual void unitDiffusionInverseMap( Path& path ) const; .... }; void EaSde::unitDiffusionInverseMap( Path& path ) const { std::transform( path.values.begin(), path.values.end(), path.values.begin(), boost::bind<double>( &sde::EaSde::unitDiffusionInverseMap, this, _1 ) ); } This code works fine. However if I use boost::bind::lambda instead of boost::bind I get: 1>Compiling... 1>sdefunctionalmc.cpp 1>c:\develop\nsde\nsde\abstracteasde.hpp(58) : error C2664: 'const boost::lambda::lambda_functor<T> boost::lambda::bind<double,const sde::EaSde*,const boost::lambda::placeholder1_type>(const Arg1 &,const Arg2 &,const Arg3 &)' : cannot convert parameter 1 from 'overloaded-function' to 'const double &' 1> with 1> [ 1> T=boost::lambda::lambda_functor_base<boost::lambda::action<3,boost::lambda::function_action<3>>,boost::tuples::tuple<const double,const sde::EaSde *const ,const boost::lambda::lambda_functor<boost::lambda::placeholder<1>>,boost::lambda::detail::bind_traits<boost::tuples::null_type>::type,boost::lambda::detail::bind_traits<boost::tuples::null_type>::type,boost::lambda::detail::bind_traits<boost::tuples::null_type>::type,boost::lambda::detail::bind_traits<boost::tuples::null_type>::type,boost::lambda::detail::bind_traits<boost::tuples::null_type>::type,boost::lambda::detail::bind_traits<boost::tuples::null_type>::type,boost::lambda::detail::bind_traits<boost::tuples::null_type>::type>>, 1> Arg1=double, 1> Arg2=const sde::EaSde *, 1> Arg3=const boost::lambda::placeholder1_type 1> ] 1> Reason: cannot convert from 'overloaded-function' to 'const double' 1> Context does not allow for disambiguation of overloaded function 1>c:\develop\nsde\nsde\abstracteasde.hpp(58) : error C2780: '_OutIt std::transform(_InIt1,_InIt1,_InIt2,_OutIt,_Fn2)' : expects 5 arguments - 4 provided 1> c:\programmi\microsoft visual studio 8\vc\include\algorithm(797) : see declaration of 'std::transform' Why in this case is boost::bind working and boost::lambda::bind not working? Where can I find more informations on the differences about the two? On a side note I'm wondering if I can expect different performance of the two implementations.... I'm actually moving everything to boost::lambda::bind to 1) avoid the conflict of boost::lambda::_1 and _1 2) have binders that are "lambda ready" if needed Thank you in advance for your reply.

3 4

Using lambda for sort
by Olaf van der Spek 10 Aug '07

10 Aug '07

Hi, I'm trying to sort a map based on second, but I get all kinds of compiler errors and I have no idea what's wrong. A simple _1 > _2 works fine, but that compares the maps themselves. Also, is there a better way to write the copy from map to vector or to sort the map in general? Note that I'm using a map because I'm counting how often an integer or string occurs. #include <boost/lambda/lambda.hpp> #include <boost/lambda/bind.hpp> #include <algorithm> #include <map> #include <vector> using namespace std; using namespace boost::lambda; int _tmain(int argc, _TCHAR* argv[]) { typedef std::map<int, int> countries_t; countries_t countries; countries[0] = 5; countries[1] = 3; countries[2] = 1; typedef vector<countries_t::const_iterator> countries1_t; countries1_t countries1; for (countries_t::const_iterator i = countries.begin(); i != countries.end(); i++) countries1.push_back(i); sort(countries1.begin(), countries1.end(), _1->second > _2->second); return 0; } ------ Build started: Project: Lambda Test, Configuration: Debug Win32 ------ Compiling... Lambda Test.cpp c:\vc\temp\lambda test\lambda test.cpp(23) : error C2819: type 'boost::lambda::lambda_functor<T>' does not have an overloaded member 'operator ->' with [ T=boost::lambda::placeholder<1> ] did you intend to use '.' instead? c:\vc\temp\lambda test\lambda test.cpp(23) : error C2039: 'second' : is not a member of 'boost::lambda::lambda_functor<T>' with [ T=boost::lambda::placeholder<1> ] c:\vc\temp\lambda test\lambda test.cpp(23) : error C2819: type 'boost::lambda::lambda_functor<T>' does not have an overloaded member 'operator ->' with [ T=boost::lambda::placeholder<2> ] did you intend to use '.' instead? c:\vc\temp\lambda test\lambda test.cpp(23) : error C2039: 'second' : is not a member of 'boost::lambda::lambda_functor<T>' with [ T=boost::lambda::placeholder<2> ] c:\vc\temp\lambda test\lambda test.cpp(23) : error C2780: 'void std::sort(_RanIt,_RanIt)' : expects 2 arguments - 3 provided c:\program files\microsoft visual studio 8\vc\include\algorithm(3109) : see declaration of 'std::sort' Lambda Test - 5 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

6 14

boost::variant/visitor problem
by Joe 10 Aug '07

10 Aug '07

Hi, Can someone help me. I have defined a boost::variant<long long,double,std::string> with a visitor which issues an increment. The visitor derived class below works fine for std::string and long long only within the visitor, but as soon as I add a double, I get an ambiguous call compile error (error below). I'm guessing when T within the prop_increment class is an int, the compiler doesn't know whether to use the long long version of the operator() or the double version. Does anyone know how I can get around this when I apply the visitor? Interestingly enough, if I add an int to the boost::variant template list the error goes away. ------ Compile Error ------ Error 44 error C2668: 'boost::detail::variant::make_initializer_node::apply<BaseIndexPair,Iterator>::initializer_node::initialize' : ambiguous call to overloaded function \boost\variant\variant.hpp 1273 ----------------------------- ------ Visitor Class ----------- class prop_increment : public boost::static_visitor<> { public: template <typename T, typename U> void operator()( T &, const U & ) const { return; } template<typename T> void operator()(T & lhs, const T& rhs) const { lhs += rhs; } }; ------------------------------------ boost::apply_visitor(prop_increment(),prop1,prop2); ---- Visitor Call ------------------- Thanks

1 0

boost::iostreams::gzip_compressor and multiple files
by Robert Caldecott 10 Aug '07

10 Aug '07

I have been experimenting with the boost::iostreams to create a gzip file, for example the following works fine: using namespace boost::iostreams; filtering_ostream out; out.push(gzip_compressor()); out.push(file_sink("test.gz", std::ios::binary)); out << "This is a gz file\n"; This will create a gz file containing a single compressed file (called 'test'). I can change the name of this internal file using a gzip_params struct and all is well. However, I want to create a single gzip file that contains multiple compressed files, each with a different filename. Does anyone know how to achieve this? Thanks in advance.

5 4

Re: [Boost-users] Serialization of hashmap
by Hansi Hansi 10 Aug '07

10 Aug '07

My system is using the dinkumware.hpp header as stdlib. There the BOOST_HAS_HASH is not set. But olso if I set this it doesn't work. Because it doesn't has the resize function and the bucket_count. Best regards Hansjörg > -----Ursprüngliche Nachricht----- > Von: boost-users(a)lists.boost.org > Gesendet: 10.08.07 08:25:39 > An: boost-users(a)lists.boost.org > Betreff: Re: [Boost-users] Serialization of hashmap > > Hansi Hansi wrote: > > > the BOOST_HAS_HASH makro wosn't set. > > OK - that macro should be set automatically by > including "config..hpp" > > I believe that I've had problem in the past in this > area. If you find out why it wasn't set, let us > know so we can fix it in the next release. > > Robert Ramaey > > > > > Best regards > > Hansjörg > > > > > > > > <hr> > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > _________________________________________________________________________ In 5 Schritten zur eigenen Homepage. Jetzt Domain sichern und gestalten! Nur 3,99 EUR/Monat! http://www.maildomain.web.de/?mc=021114

1 0

boost static assert and is_base_of question.
by chun ping wang 10 Aug '07

10 Aug '07

Hi, how would I ensured that class U of template class is a dervied class of boost::operators<U> using BOOST_STATIC_ASSERT and boost::is_base_of... template <T> myFunc(const T& a) { typedef boost::operators<T> operatorT; BOOST_STATIC_ASSERT(is_integral<T>::value || is_base_of<operatorT, T>::value); // ... other codes. } doing this gives me an error. arguments, but takes just 1 ./cs512/c++/cppdef/DiffieHellman.cpp: In function `T boost::random_prime(boost:: function<bool ()(const T&, const T&), std::allocator<void> >, int)': ./cs512/c++/cppdef/DiffieHellman.cpp:23: error: `BOOST_STATIC_ASSERT' was not de clared in this scope ./cs512/c++/cppdef/DiffieHellman.cpp:49:78: macro "BOOST_STATIC_ASSERT" passed 2 arguments, but takes just 1 ./cs512/c++/cppdef/DiffieHellman.cpp: In function `boost::tuples::tuple<T, T, bo ost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boos t::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost: :tuples::null_type, boost::tuples::null_type> boost::dh_init(const boost::any&)' : ./cs512/c++/cppdef/DiffieHellman.cpp:49: error: `BOOST_STATIC_ASSERT' was not de clared in this scope ./cs512/c++/cppdef/DiffieHellman.cpp:64:78: macro "BOOST_STATIC_ASSERT" passed 2 arguments, but takes just 1 ./cs512/c++/cppdef/DiffieHellman.cpp: In function `T boost::dh_secret(const T&, const T&, const T&)': ./cs512/c++/cppdef/DiffieHellman.cpp:64: error: `BOOST_STATIC_ASSERT' was not de clared in this scope make[1]: *** [lib/DiffieHellman.o] Error 1 make[1]: Leaving directory `/c/CPW/cs_classes' make: *** [all-before] Error 2

2 1

Re: [Boost-users] Serialization of hashmap
by Hansi Hansi 10 Aug '07

10 Aug '07

> > > Hansi Hansi wrote: > > Hello, > > > > I don't know If I'm wrong. To install boost I have used the installer > > from boost-consulting. At the moment I'm using version 1.34.0. > > I have set the configuration makros in the follwing way > > > > #define BOOST_HAS_HASH > > #define BOOST_STD_EXTENSION_NAMESPACE stdext > > #define STD BOOST_STD_EXTENSION_NAMESPACE > > You shouldn't have to set any macros. These should be set by > boost/config.hpp which sets them properly for each compiler. > I don't know if these are in fact set. If not, > the fact that these tests are passing on my system and on the > release tests wouldn't mean much. > > I'm too busy right now to look further into it. > > Robert Ramey > > the BOOST_HAS_HASH makro wosn't set. Best regards Hansjörg > > > > The problem is that during compiling I get 2 errors: > > > > Error 133 error C2039: 'resize' : is not a member of > > 'stdext::hash_map<_Kty,_Ty,_Tr>' > > C:\boost_1_34_0\boost\serialization\hash_collections_load_imp.hpp 46 > > Error 134 error C2039: 'bucket_count' : is not a member of > > 'stdext::hash_map<_Kty,_Ty,_Tr>' > > C:\boost_1_34_0\boost\serialization\hash_collections_save_imp.hpp 43 > > > > The test program doesn't work to compile too. There are problems > > with the following lines: > > > > namespace BOOST_STD_EXTENSION_NAMESPACE { > > template<> > > struct hash<random_key>{ > > <<<<<<<<<------------- line 156 > > std::size_t operator()(const random_key& r) const { > > return (std::size_t)r; > > } > > }; > > } // namespace BOOST_STD_EXTENSION_NAMESPACE > > > > > > Error 9 error C2143: syntax error : missing ';' before '<' > > c:\boost_1_34_0\libs\serialization\test\test_map.cpp 156 > > > > Is there some other makro that I have to define? > > > > Best Regards and many thanks for your help > > > > Hansjörg > > > >> -----Ursprüngliche Nachricht----- > >> Von: boost-users(a)lists.boost.org > >> Gesendet: 09.08.07 08:54:35 > >> An: boost-users(a)lists.boost.org > >> Betreff: Re: [Boost-users] Serialization of hashmap > > > > > >> > >> There is a test program - test_map which should demonstrate the > >> functionality. > >> > >> It depends upon standard boost macros for stdext: so if the test > >> doesnt invoke the hash map, you might check to see if the config > >> system is correct. > >> > >> Let me know what you find out. > >> > >> Robert Ramey > >> > >> Hansi Hansi wrote: > >>> Hello, > >>> > >>> Sorry I have forgotten to write the subject in the last post. > >>> > >>> is there a possibility to serialize a hash_map with the vc8.0 > >>> compiler? this compiler has defined a hash_map under the stdext > >>> namespace. It seems that the implementation in boost doesn't work at > >>> the moment for this class. > >>> > >>> Or is there another hash_map implementation available which can be > >>> serialized? > >>> > >>> Best regards > >>> Hansjörg > >>> > >>> > >>> _____________________________________________________________________ > >>> Der WEB.DE SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu > >>> sparen! > >>> http://smartsurfer.web.de/?mc=100071&distributionid=000000000066 > >> > >> > >> > >> > >> > >> <hr> > >> _______________________________________________ > >> Boost-users mailing list > >> Boost-users(a)lists.boost.org > >> http://lists.boost.org/mailman/listinfo.cgi/boost-users > >> > > > > > > __________________________________________________________________________ > > Erweitern Sie FreeMail zu einem noch leistungsstärkeren > > E-Mail-Postfach! > > Mehr Infos unter http://produkte.web.de/club/?mc=021131 > > > > > > <hr> > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > _______________________________________________________________________ Jetzt neu! Schützen Sie Ihren PC mit McAfee und WEB.DE. 3 Monate kostenlos testen. http://www.pc-sicherheit.web.de/startseite/?mc=022220

2 1

[Serialization] Problem serialization of derived classes
by Andreas Willich 09 Aug '07

09 Aug '07

Hi there! I have a problem with the code in the attachment. I followed the documentation and the examples, but I did not get the code to work. Gcc produces a lot of failures that something is already instantiated in header files of the serialization library. Has someone a idea what I am doing wrong? My gcc version is 4.1.1-r3 and I am working on a gentoo x86 box. Andreas Willich

4 5

is asio's io_service required for any socket related call?
by pete＠mu.org 09 Aug '07

09 Aug '07

Hi, I 've been doinking around with asio for a few weeks, and I've run into an issue I can't seem to wrap my head around. I've been playing with some code that originally was meant to pound a server with a large amount of packets for benchmarking purposes. It uses threads to launch hundreds of threads per second. When I replaced the old socket code with asio, and used a single io_service with run being called within each thread, I run out of file descriptors very quickly, and if I use a single io_service within each thread it's the same thing but the performance seems worse. Needless to say, this seems like a real limitation and I'm hoping I'm just being limited by my own misunderstanding, because I'm really enjoying the portability of asio. The docs that are there seem great, but there seems to be a lot more the library can do that I am missing out on, and I think the docs seem like they are not mentioning a lot of what asio an do. Can someone point me in the right direction for launching 1-to-N threads with a single send_to and a single receive_from within each thread that doesn't take the hit I'm seeing? It seems to me, that it's obvious that the io-service design is the difference, because I don't get the issue at all when I use plain old sockets, and the OS thread limit is then the only limitation. Any help would be greatly appreciated. FYI, I've done most of my experimenting on Linux and OSX. Thanks, Pete

1 0

boost.thread library and the thread is running
by Mirosław Makowiecki 09 Aug '07

09 Aug '07

Is it boost.thread library have a ability by next of its I is allowed to find out what it is running? How do it? Thanks in advice.

1 0

Re: [Boost-users] [boost::fusion v2 and xpressive] versioning conflicts...
by Ovanes Markarian 09 Aug '07

09 Aug '07

Eric, many thanks for you help. I will try doing it until Monday. Some additional question: fusion v2 will be a separate lib, so the path boost/fusion instead of boost/spirit/fusion is fine? With Kind Regards, Ovanes Markarian On Thu, August 9, 2007 21:02, Eric Niebler wrote: > > Ovanes Markarian wrote: >> Hello, >> >> I am using fusion v2 in my project and first would like to thank for the great lib. I installed this lib into the boost/fusion directory. >> >> Today I started using xpressive lib (which is also a great one!!!). Unfortunately xpressive broke >> my compilation, because it includes things from boost/spirit/fusion and my code includes headers from boost/fusion. Now my assumption: AFAIK spirit/fusion contains version 1. Since I would like to use version 2 I can not simply copy it into the spirit directory, since it can break other things like wave. Is it correct? If yes, does anyone have suggestions on how I should deal with this issues? > > > I can infer from this that you're using boost 1.34.1 or earlier, and you've copied boost.fusion from svn HEAD into the tree, right? Xpressive isn't expecting to find Fusion v2 in Boost 1.34, hence the problem. You'll need to hack on xpressive a bit to make this work. In > xpressive_fwd.hpp, you should add something like > > #if BOOST_VERSION >= 103500 > #ifndef BOOST_XPRESSIVE_FUSION_V2 > #define BOOST_XPRESSIVE_FUSION_V2 > #endif > #endif > > Then everywhere xpressive conditionally includes fusion v1 or v2, you should check BOOST_XPRESSIVE_FUSION_V2 instead of the boost version. You'll need to do something similar in proto_fwd.hpp (#define > BOOST_PROTO_FUSION_V2) and all of proto's headers. Then you'll be ableto force the issue by compiling with BOOST_XPRESSIVE_FUSION_V2 and > BOOST_PROTO_FUSION_V2 defined. > > If you do all this and submit a patch, I'll accept it. > > > -- > Eric Niebler > Boost Consulting > www.boost-consulting.com > > The Astoria Seminar ==> http://www.astoriaseminar.com > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > With Kind Regards, Ovanes Markarian

2 1

Subject: [Serialization] Why is it not possible to serialize this structure through a pointer?
by Oliver Kania 09 Aug '07

09 Aug '07

Hello, I have the following struct: struct CUBE_INFO { friend class boost::serialization::access; long cube; std::string ncube; UINT number_dimensions; DIMENSION_LIST dimensions; long double number_cells; long double number_filled_cells; enum STATUS { UNLOADED = 0, LOADED, CHANGED } status; enum TYPE { NORMAL = 0, SYSTEM, ATTRIBUTE } type; friend std::istream& operator>>( std::istream& in, CUBE_INFO& cubeInfo ); friend std::ostream& operator<<( std::ostream& out, const CUBE_INFO& cubeInfo ); private: template<class Archive> void serialize( Archive &ar, const unsigned int version ) { ar & cube; ar & dimensions; ar & ncube; ar & number_cells; ar & number_dimensions; ar & number_filled_cells; ar & status; ar & type; } }; here, DIMENSION_LIST is an STL-vector of longs. I am including #include <boost/serialization/vector.hpp> #include <boost/serialization/access.hpp> I try to comple the code below (MS VisualStudio 8, boost 1.34) #include <fstream> #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include <string> #include "../Palo/Cache/AbstractCache.h" #include "../Palo/Cache/CubeCache.h" #include "../Palo/Cache/CubesCache.h" #include "../Palo/types.h" using namespace jedox::palo; int main(int argc, char* argv[]) { //string filename("SerializeTest"); CUBE_INFO* c = new CUBE_INFO(); std::ofstream ofs("filename"); //std::ofstream ofs("filename" ); // save data to archive { boost::archive::text_oarchive oa( ofs ); // write class instance to archive oa << ( c ); // archive and stream closed when destructors are called } return 0; } The resulting error message is: >f:\lib\x32\include\boost\archive\detail\oserializer.hpp(567) : error C2027: use of undefined type 'boost::STATIC_ASSERTION_FAILURE<x>' 1> with 1> [ 1> x=false 1> ] 1> f:\lib\x32\include\boost\archive\basic_text_oarchive.hpp(78) : see reference to function template instantiation 'void boost::archive::save<Archive,T>(Archive &,T &)' being compiled 1> with 1> [ 1> Archive=boost::archive::text_oarchive, 1> T=jedox::palo::CUBE_INFO * 1> ] regards, Oliver

3 2

[boost::fusion v2 and xpressive] versioning conflicts...
by Ovanes Markarian 09 Aug '07

09 Aug '07

Hello, I am using fusion v2 in my project and first would like to thank for the great lib. I installed this lib into the boost/fusion directory. Today I started using xpressive lib (which is also a great one!!!). Unfortunately xpressive broke my compilation, because it includes things from boost/spirit/fusion and my code includes headers from boost/fusion. Now my assumption: AFAIK spirit/fusion contains version 1. Since I would like to use version 2 I can not simply copy it into the spirit directory, since it can break other things like wave. Is it correct? If yes, does anyone have suggestions on how I should deal with this issues? Detailed compiler errors: E:\libraries\boost\include\boost/fusion/support/detail/access.hpp(24) : error C2953: 'boost::fusion::detail::ref_result' : class template has already been defined E:\libraries\boost\include\boost/spirit/fusion/detail/access.hpp(23) : see declaration of 'boost::fusion::detail::ref_result' E:\libraries\boost\include\boost/fusion/support/detail/access.hpp(34) : error C2953: 'boost::fusion::detail::cref_result' : class template has already been defined E:\libraries\boost\include\boost/spirit/fusion/detail/access.hpp(29) : see declaration of 'boost::fusion::detail::cref_result' E:\libraries\boost\include\boost/fusion/support/detail/access.hpp(40) : error C2953: 'boost::fusion::detail::non_ref_parameter' : class template has already been defined E:\libraries\boost\include\boost/spirit/fusion/detail/access.hpp(37) : see declaration of 'boost::fusion::detail::non_ref_parameter' E:\libraries\boost\include\boost/fusion/support/detail/access.hpp(52) : error C2953: 'boost::fusion::detail::call_param' : class template has already been defined E:\libraries\boost\include\boost/spirit/fusion/detail/access.hpp(43) : see declaration of 'boost::fusion::detail::call_param' With Kind Regards, Ovanes Markarian

3 3

BoostBook survey.
by Rene Rivera 09 Aug '07

09 Aug '07

If any of you follow the wxWidgets dev list you might have noticed they are thinking of changing doc format. I pointed out BoostBook as a possibility. Obviously they would like to see non-Boost uses of BoostBook. So I'm asking the wonderfully varied Boost user community... * Do you use BoostBook in some way? * If so, could you provide an example of how you use it? If you want I can find a place in our growing list of Boost users <http://www.boost.org/doc/html/who_s_using_boost_.html>. -- -- Grafik - Don't Assume Anything -- Redshift Software, Inc. - http://redshift-software.com -- rrivera/acm.org - grafik/redshift-software.com -- 102708583/icq - grafikrobot/aim - grafikrobot/yahoo

1 0

Re: [Boost-users] Boost-users Digest, Vol 1352, Issue 1
by Pranckevicius, Tadas 09 Aug '07

09 Aug '07

> I think I know which ones. These are cryptic error messages. They > happened in my case because of the include order. > I work under VS 2005 with SP2 (whcih you should install by the way). > Make sure you include the system headers (like windows.h) before the > boost headers. VS 2005 SP2? That's strange I cannot find any info about this service pack: http://msdn2.microsoft.com/en-us/vstudio/Aa718359.aspx Tadas

1 0

Re: [Boost-users] Serialization of hashmap
by Hansi Hansi 09 Aug '07

09 Aug '07

Hello, I don't know If I'm wrong. To install boost I have used the installer from boost-consulting. At the moment I'm using version 1.34.0. I have set the configuration makros in the follwing way #define BOOST_HAS_HASH #define BOOST_STD_EXTENSION_NAMESPACE stdext #define STD BOOST_STD_EXTENSION_NAMESPACE The problem is that during compiling I get 2 errors: Error 133 error C2039: 'resize' : is not a member of 'stdext::hash_map<_Kty,_Ty,_Tr>' C:\boost_1_34_0\boost\serialization\hash_collections_load_imp.hpp 46 Error 134 error C2039: 'bucket_count' : is not a member of 'stdext::hash_map<_Kty,_Ty,_Tr>' C:\boost_1_34_0\boost\serialization\hash_collections_save_imp.hpp 43 The test program doesn't work to compile too. There are problems with the following lines: namespace BOOST_STD_EXTENSION_NAMESPACE { template<> struct hash<random_key>{ <<<<<<<<<------------- line 156 std::size_t operator()(const random_key& r) const { return (std::size_t)r; } }; } // namespace BOOST_STD_EXTENSION_NAMESPACE Error 9 error C2143: syntax error : missing ';' before '<' c:\boost_1_34_0\libs\serialization\test\test_map.cpp 156 Is there some other makro that I have to define? Best Regards and many thanks for your help Hansjörg > -----Ursprüngliche Nachricht----- > Von: boost-users(a)lists.boost.org > Gesendet: 09.08.07 08:54:35 > An: boost-users(a)lists.boost.org > Betreff: Re: [Boost-users] Serialization of hashmap > > There is a test program - test_map which should demonstrate the > functionality. > > It depends upon standard boost macros for stdext: so if the test > doesnt invoke the hash map, you might check to see if the config system > is correct. > > Let me know what you find out. > > Robert Ramey > > Hansi Hansi wrote: > > Hello, > > > > Sorry I have forgotten to write the subject in the last post. > > > > is there a possibility to serialize a hash_map with the vc8.0 > > compiler? this compiler has defined a hash_map under the stdext > > namespace. It seems that the implementation in boost doesn't work at > > the moment for this class. > > > > Or is there another hash_map implementation available which can be > > serialized? > > > > Best regards > > Hansjörg > > > > > > _____________________________________________________________________ > > Der WEB.DE SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! > > http://smartsurfer.web.de/?mc=100071&distributionid=000000000066 > > > > > > <hr> > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > __________________________________________________________________________ Erweitern Sie FreeMail zu einem noch leistungsstärkeren E-Mail-Postfach! Mehr Infos unter http://produkte.web.de/club/?mc=021131

2 1

Memory pool management (v1-34-1)
by cisjar 09 Aug '07

09 Aug '07

I am using memory pool objects and I had a little trouble when ran first time my multi-threaded application under Linux. I looked at sources (detail/mutex.hpp) and in my opinion an automatic recognition the multi-thread mode is done improperly. In my project I used only headers from pool library and I had to explitly defined the BOOST_HAS_THREADS macro. There is not any information about it in documentation. From other boost libraries I know that is not intended to define this macro by users. cisjar

1 0

Serialization of hashmap
by Hansi Hansi 09 Aug '07

09 Aug '07

Hello, Sorry I have forgotten to write the subject in the last post. is there a possibility to serialize a hash_map with the vc8.0 compiler? this compiler has defined a hash_map under the stdext namespace. It seems that the implementation in boost doesn't work at the moment for this class. Or is there another hash_map implementation available which can be serialized? Best regards Hansjörg _____________________________________________________________________ Der WEB.DE SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! http://smartsurfer.web.de/?mc=100071&distributionid=000000000066

2 1

Fwd: Re: timeout events in Boost.Statechart
by Chris Paulse 08 Aug '07

08 Aug '07

>> I ended up implementing timeout support with a WM_TIMER handler in the >> parent of the state machine class. ... > > Does the WM_TIMER handler really add the event to the queue of the > state_machine subclass object? If so, then you might have introduced > a race condition. WM_TIMER handlers are called in a dedicated thread, > right? >From my understanding of the documentation of SetTimer and my use of it, everything should be working from the same thread (WM_TIMER messages are posted to the main thread's message queue, where they are processed while the thread is idle). So, I don't think there's a race condition. >> Also, like the Camera example, I implemented a >> post_event in the >> constructor/entry of some states, which also requires derivation >> from state, > > Correct. > >> and awkward instancing of the event. > > I don't understand. You mean the special constructor you have to add > to the state, right? Well, that, but more importantly, the cast inside of the post_event. Making calls to post_event from a constructor/enter seem like a fairly typical use case. >> Would using methods (Entry/Exit) >> instead of >> the constructor/destructor ease some of these problems? > > This is a somewhat controversical topic. During formal review there > were a few people who favored entry() and exit() functions over the > current ctor/dtor design. Thanks for the explanation (removed for brevity), and the sample code!

2 1

[program_options] patch - optional argument support (gnu getopt_long style)
by Bryan Green 08 Aug '07

08 Aug '07

Attached is a patch to program_options that implements optional argument support, in the style of GNU getopt_long. It adds one new method to 'value_type': 'implicit_value()'. The idea is that, if the option is given without an argument, it is assigned an "implicit" value. Otherwise, if the long-option is given an explicit argument via the equals sign (--arg=value), or the short-option is given an adjacent argument (-avalue), the explicit value will override the implicit one. For example: desc.add_options() ("proxy,p", value<int>(&proxy_port)->implicit_value(DefaultProxyPort), "run proxy service") ; ... if (vm.count("proxy")) enable_the_proxy(proxy_port); ./prog --proxy --opt2 --opt3 -> enables proxy on default port. ./prog --proxy=9000 --opt2 --opt3 -> enables proxy on port 9000. ./prog --opt2 --opt3 -> does not enable the proxy. -Bryan

3 10

Subject : [Serialization] linker problem, serialization method cannot be found.
by Oliver Kania 08 Aug '07

08 Aug '07

Hello and thanks for the help I received so far. here is my current problem: The class I try to serialize is: class LIBPALO_NG_CLASS_EXPORT CubeCache : public CUBE_INFO { public: friend class boost::serialization::access; CubeCache(); ~CubeCache(); void setSequenceNumber( unsigned int sequenceNumber ) { m_SequenceNumber = sequenceNumber; } unsigned int getSequenceNumber() const { return m_SequenceNumber; } private: unsigned int m_SequenceNumber; template<class Archive> void serialize( Archive &ar, const unsigned int version ); }; the cpp file looks as follows: #include "CubeCache.h" #include <boost/serialization/base_object.hpp> namespace jedox { namespace palo /* palo */ { template<class Archive> void CubeCache::serialize( Archive &ar, const unsigned int version ) { // save/load base class information ar & boost::serialization::base_object<CUBE_INFO>( *this ); ar & m_SequenceNumber; } CubeCache::CubeCache(){;} CubeCache::~CubeCache(){;} } } /* jedox */ The CUBE_INFO structure serializes just fine. There are no linkage problems with the following code: int main( int argc, char* argv[] ) { CUBE_iNFO* const c = new CUBE_INFO(); std::ofstream ofs("filename"); // save data to archive { boost::archive::text_oarchive oa( ofs ); // write class instance to archive oa << ( c ); // archive and stream closed when destructors are called } return 0; } However, when I use CubeCache instead of CUBE_INFO in the above code, i get a linkage error: ====================================================================== libpalo_ng.obj : error LNK2019: unresolved external symbol "private: void __thiscall jedox::palo::CubeCache::serialize<class boost::archive::text_oarchive>(class boost::archive::text_oarchive &,unsigned int)" ... ====================================================================== There are no linkage problems with the library when i do not use boost::serialization. I guess this happens when the linker tries to link with the serialization library. LIBPALO_NG_CLASS_EXPORT is defined as: # define LIBPALO_NG_CLASS_EXPORT __declspec(dllexport) Regards, Oliver

3 2

[serialization] Writing an old version of a class
by Pfligersdorffer, Christian 08 Aug '07

08 Aug '07

Hello Robert, hello all, I know it is stated in the boost::serialization library documentation that per definition always the latest version of a class goes to the archive. I wonder if there is a way to change this behaviour and choose the version number for my class at runtime. Obviously this feature would be useful in a system of two dependent modules where either the producer or the consumer could by updated to a newer version without the other one being neccessarily updated too. Maybe this has already been discussed but I could not find anything about it on the web. However my strong suspicion is that there is no such option within the library and I will have to provide a solution within the affected classes. Another thing: I specialize boost::archive::detail::heap_allocator<T> for my types to use my own memory management :-) Any objection to that? Finally I want to thank Robert Ramey for his fabulous library and his always timely and helpful answers. I think from the user perspective he stands as a positive example for others. Regards, -- Christian Pfligersdorffer EOS Software Engineering

2 3

<kein Betreff>
by Hansi Hansi 08 Aug '07

08 Aug '07

Hello, is there a possibility to serialize a hash_map with the vc8.0 compiler? this compiler has defined a hash_map under the stdext namespace. Or is there another hash_map implementation available which can be serialized? Best regards Hansjörg __________________________________________________________________________ Erweitern Sie FreeMail zu einem noch leistungsstärkeren E-Mail-Postfach! Mehr Infos unter http://produkte.web.de/club/?mc=021131

1 0

Serialization & enums
by Gross, Steve 07 Aug '07

07 Aug '07

Hi folks. I'm learning the basics of the serialization library right now. I'd like to know if there's a known tactic for archiving enums with textual tokens, rather than the int value itself. For instance, consider the following code: I set up an enum called status_t, and a class Foo that has a status_t as a data member. In Foo's serialize function, I record the status_t (myStatus). enum status_t { ON, OFF }; class Foo { status_t myStatus; friend class boost::serialization::access; template<class Archive> serialize(...) { ar & BOOST_SERIALIZATION_NVP(myStatus); } }; The xml output file looks sort of like this: <Foo> <myStatus>0</myStatus> </Foo> The file that is generated when serialize() is invoked certainly works, but the value for myStatus appears as an int. What if I want to convert the int to a string in the archive? That is, I want the xml file to look like this: <Foo> <myStatus>ON</myStatus> </Foo> Are there any good strategies for doing this? Thanks, --Steve (sgross(a)sjm.com)

1 0

term by term product of vectors (or proxies thereof)
by e r 07 Aug '07

07 Aug '07

hi, what's the best way to achieve x*=y? where x and y are vectors (or proxies) of identical size? although i wrote a function (below) i hope there's already some ublas related facility to do so. template<typename D> class Op_product_term_by_term{ public: Op_product_term_by_term(D& dest):iter(dest.begin()),end(dest.end()){}; void operator()(double elem); private: typename D::iterator iter; typename D::iterator end; }; template<typename D> void Op_product_term_by_term<D>::operator()(double elem){ if(iter<end){ *(iter++)*=elem; }else{ throw; }; }; template<typename D, typename B> void product_term_by_term(D& dest,const B& by){ if(dest.size()==by.size()){ for_each(by.begin(),by.end(),Op_product_term_by_term<D>(dest)); }else{ throw; }; }; ps: should i post this kind of ad in boost/ublas or boost/users?

1 0

[DateTime] Functions parsing date/time values from wstring missing?
by Boris 07 Aug '07

07 Aug '07

According to http://www.boost.org/doc/html/date_time/details.html#date_time.changes there have been functions added to Boost.DateTime (between Boost 1.31 to 1.32) to convert date and time classes to wstring. However I can't find any functions to parse date and time values from wstring. There is for example to_iso_extended_wstring() but no from_simple_wstring(). Am I missing something? Boris

1 0

[boost][graph] write_graphviz problem
by David Callu 07 Aug '07

07 Aug '07

Hi, I try to write my graph to std::cout with boost::write_graphviz. In the example boost/libs/graph/example/graphviz.cpp, the graph used is a boost::adjacency_list<vecS, vecS, directedS, property<vertex_name_t, std::string>, property<edge_weight_t, double> > and all work fine. my graph is a boost::adjacency_list<listS, listS, bidirectedS, property<my_vertex_t, my_vertex>, property<my_edge_t, my_edge>, property<my_graph_t, my_graph> , listS > If a do "write_graphviz(std::cout, g);" I have a very big error. (why BGL didn't use boost concept check ???) I search in boost code and i found !!! In the file boost/graph/graphviz.hpp line 257 (boost 1.34) "out << get(vertex_id, *i);" so write_graphviz function get the vertex property with the tag of type vertex_id. By default, the type vertex_id is the enum boost::vertex_index which do reference to the type boost::vertex_index_t; This property is intrinsically in the type boost::adjacency_list<vecS, vecS> because the vertex_descriptor is the index of the vertex. And so all work fine with the function write_graphviz With the type boost::adjacency_list<vecS, listS>, this property is not available. TOOOOOO In the complete signature function : void write_graphviz(std::ostream &, const VertexListGraph & g vertexPropertyWrite vpw, EdgePropertyWriter epw, GraphPropertyWriter gpw, VertexID vertex_id); I can give the property_tag to used in the function. But, In opposition to other BGL algorithm which accept an external PropertyMap, this property must be in the graph. And I don't want to add a index property. Question : How to use write_graphviz algorithm with boost::adjacency_list<listS, listS> ? Is there a magic boost property tag to use with a boost::adjacency_list<listS, listS> like the boost::vertex_index_t tag and the boost::adjacency_list<vecS, vecS> is there another solution ?? Thank David Callu

2 2

[Fusion] Is there a version of fusion that works with vanilla 1.34.1?
by Ames, Andreas (Andreas) 07 Aug '07

07 Aug '07

Hi, is there a version of fusion that works with vanilla 1.34.1? TIA, aa -- Andreas Ames | Programmer | Comergo GmbH | ames AT avaya DOT com Sitz der Gesellschaft: Stuttgart Registergericht: Amtsgericht Stuttgart - HRB 22107 Geschäftsführer: Andreas von Meyer zu Knonow, Udo Bühler, Thomas Kreikemeier

3 5

[iterator_adaptor] Accessing base class
by Mark Ruzon 07 Aug '07

07 Aug '07

I have defined an iterator adaptor called skip_iterator. I found that I have to write: skip_iterator() : skip_iterator::iterator_adaptor_(0), m(1) {} rather than skip_iterator() : iterator_adaptor_(0), m(1) {} even though iterator_adaptor_ is a protected typedef inside iterator_adaptor. Will someone explain why I have to qualify the name? Thanks, Mark Ruzon

4 3

order of iterators in multi_index container
by boost＠larroy.com 07 Aug '07

07 Aug '07

Hi I was using multi_index nicely and then I wondered that although iterators are not invalidated when calling replace or modify, could it be that if I'm modifying inside a loop then incrementing the iterator no longer makes it iterate through all elements because of the index reordering? Regards. -- Pedro Larroy Tovar Promax R&D Lab

4 6

Fwd: Re: timeout events in Boost.Statechart
by Andreas Huber 07 Aug '07

07 Aug '07

Hi Chris, > I ended up implementing timeout support with a WM_TIMER handler in > the > parent of the state machine class. States that can have a timeout > event > just pass their timeout duration to the state machine via > context<>, which > in turn calls SetTimer in the parent class. The WM_TIMER handler > adds a > timeout event to the state machine's queue. Does the WM_TIMER handler really add the event to the queue of the state_machine subclass object? If so, then you might have introduced a race condition. WM_TIMER handlers are called in a dedicated thread, right? > Just to comment on the design, it requires that I declare state > classes with > "state" base class instead of simple_state, as I have to perform > the > context<> cast in the constructor/entry of the new state in order > to set up > a timeout. Correct. > Also, like the Camera example, I implemented a > post_event in the > constructor/entry of some states, which also requires derivation > from state, Correct. > and awkward instancing of the event. I don't understand. You mean the special constructor you have to add to the state, right? > Unfortunately, I'm in feasibility testing, and haven't had an > opportunity to > closely examine the implementation. If you think there's something > I'm > missing, please let me know. See above, WM_TIMER should probably not call state_machine.process_event. Instead you should use asynchronous_machine and queue the event through the scheduler, which is thread-safe. > Would using methods (Entry/Exit) > instead of > the constructor/destructor ease some of these problems? This is a somewhat controversical topic. During formal review there were a few people who favored entry() and exit() functions over the current ctor/dtor design. This is related to the debate whether one should initialize everything in the constructor or do (almost) nothing in the constructor and have the client call Init() right after construction. Sure, in our case entry() would be automatically called by the library immediately after construction but it still runs counter to established C++ practice. The problem with entry() is that it forces you to losen your class invariants, e.g. timerId below can no longer be const, since context<Machine>.StartTimer() could no longer be called in the ctor (where access via context would be impossible) but only in entry(). struct MyState : sc::state<MyState, Machine> { int count_; const int timerId_; MyState(my_context ctx) : my_base(ctx), count_(0), timerId_(context<Machine>.StartTimer(3000)) { // additional stuff } ~MyState() { context<Machine>.StopTimer(timerId_); } } Regards, Andreas > On 8/3/07, Andreas Huber <ahd6974-boostorg(a)yahoo.com> wrote: > > > > Hi Chris > > > > > Since timeouts are so common in state machine applications, do > you > > > think it > > > would make sense to support them as a specific reaction type? > > > > The necessary infrastructure for time events is quite > significant, > > see > > > > > <http://www.boost.org/libs/statechart/doc/uml_mapping.html#TimeEvent> > > > > You basically either need an OS that supports timed callbacks, or > > need to implement your own scheduler, which supports the passing > of a > > time at which a given event must be dispatched. Given the lacking > > primitives in C++, both options require significant platform > > abstraction effort. I always had the hope that either > Boost.Thread or > > a futures library would provide such primitives but to my > knowledge > > nothing has so far materialized. I *guess* Asio does offer such > > primitives but I have a hard time to justify that dependency just > for > > a time event implementation. > > > > To cut a long story short, for now you need to implement time > event > > support yourself :-/. > > > > HTH, > > > > Andreas > > > > P.S. I think this information is also interesting for other boost > > users, so unless you object I'll post this message on the > Boost.Users > > list tomorrow. > >

1 0

simple_ls.cpp build issues
by Grattan, Steven 07 Aug '07

07 Aug '07

Hi, I'm new to the boost libraries and wanted to write something that would give me the names of all the entries in a directory in a platform independent way. Having looked at the filesystem facilities provided with boost I decided that this is just what I need and downlaoded simple_ls.cpp just to check I could compile it before going any further. I'm using Microsoft Visual Studio 2005 Express Edition and I get a few compile errors when I tries to build it. Maybe I'm missing something here but the error messages seem to reflect the reality since the items it can't find don't exist in the boost files provided - I'm using boost 1.3.3.1 Here is the output from the compiler: 1>------ Build started: Project: boostFileSystem, Configuration: Debug Win32 ------ 1>Compiling... 1>simple_ls.cpp 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(51) : error C2039: 'status' : is not a member of 'boost::filesystem::path' 1> x:\3rdpartytools\boost_1_33_1\boost\filesystem\path.hpp(34) : see declaration of 'boost::filesystem::path' 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(54) : error C2273: 'function-style cast' : illegal as right side of '->' operator 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(54) : error C2228: left of '.leaf' must have class/struct/union 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(56) : error C2039: 'is_regular' : is not a member of 'boost::filesystem' 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(56) : error C2039: 'status' : is not a member of 'boost::filesystem::path' 1> x:\3rdpartytools\boost_1_33_1\boost\filesystem\path.hpp(34) : see declaration of 'boost::filesystem::path' 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(56) : error C3861: 'is_regular': identifier not found 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(59) : error C2273: 'function-style cast' : illegal as right side of '->' operator 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(59) : error C2228: left of '.leaf' must have class/struct/union 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(64) : error C2273: 'function-style cast' : illegal as right side of '->' operator 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(64) : error C2228: left of '.leaf' must have class/struct/union 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(71) : error C2273: 'function-style cast' : illegal as right side of '->' operator 1>z:\visual studio 2005\projects\boostfilesystem\boostfilesystem\simple_ls.cpp(71) : error C2228: left of '.leaf' must have class/struct/union 1>Build log was saved at "file://\\sw620_f\grattans$\Visual Studio 2005\Projects\boostFileSystem\boostFileSystem\Debug\BuildLog.htm" 1>boostFileSystem - 12 error(s), 0 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== Any help would be much appreciated, Steve Grattan This email (including attachments) is confidential and is solely intended for the addressee. Unless you are the addressee, you may not read, use or store this email in any way, or permit others to. If you have received it in error, please contact Visa Europe on +44 (0)20 7937 8111.

2 2

Problem with mpl::joint_view working on two mpl::maps
by Martin Apel 07 Aug '07

07 Aug '07

Hi *, I have two mpl maps like this: typedef map<pair<int_<1>, int_<42> >, pair<int_<2>, int_<43> >, pair<int_<3>, int_<44> > > Map1; typedef map<pair<int_<4>, int_<44> >, pair<int_<5>, int_<45> >, pair<int_<6>, int_<46> > > Map2; I try to join them using "joint_view" as follows: typedef joint_view<Map1, Map2>::type JointMap; which works fine. Then I do std::cout << at<JointMap, int_<2> >::type::value << "\n"; which gives the following compiler error: error: 'value' is not a member of 'boost::mpl::pair<mpl_::int_<3>, mpl_::int_<44> >' I tried this with gcc 3.4.6 and 4.2 under Linux, Boost version is 1.34.0. It seems "at" returns the entry after the searched entry, and not only the right half, but the complete pair. Has anybody got any hints on this? To me it looks like a bug in MPL, but I might be wrong. Best Regards, Martin ____________ Virus checked: AVKB 17.327 from 06.08.2007

1 0

Re: [Boost-users] Boost-users Digest, Vol 1352, Issue 1
by Vial, Florent 07 Aug '07

07 Aug '07

>> I?ve installed Boost Libary 1.34.0 >> I?m working with VS 2005 SP1. >> If I try to include any of the boost *.hpp files I get more than 100 >> errors in the files "memory" and "algorithm". I think this errors >> first >What errors? I think I know which ones. These are cryptic error messages. They happened in my case because of the include order. I work under VS 2005 with SP2 (whcih you should install by the way). Make sure you include the system headers (like windows.h) before the boost headers. Hope this helps, Regards, Florent Arnold & Richter Cine Technik GmbH & Co. Betriebs KG Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRA 57918 Personlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH Sitz: Munchen - Registergericht: Amtsgericht Munchen - Handelsregisternummer: HRB 54477 Geschaftsfuhrer: Prof. Dr. Dejan Ilic; Franz Kraus; Jens Schafer Beiratsvorsitzender: Prof. Dr. Hans-Jorg Bullinger

1 0

Problem including hpp Headers
by Wolfgang Issovits 07 Aug '07

07 Aug '07

Hello! I´ve installed Boost Libary 1.34.0 I´m working with VS 2005 SP1. If I try to include any of the boost *.hpp files I get more than 100 errors in the files "memory" and "algorithm". I think this errors first occoured, after installing SP1 for VS. Does anyone has any idea why this errors occour?

2 2

why is there no ChangeLog ? (and tools to create/update one)
by Vincent Torri 07 Aug '07

07 Aug '07

Hey, As a user, I often wanted to see what is fixed in a library. As there is no ChangeLog (afaics), I have to look at the commits in cvs web (in svn, now), which is not very simple to use. So I wanted to know why there were no ChangeLog. I know some other big projects, and they use tools to create and commit automatically a ChangeLog. Here are 2 of them: http://www.buzztard.org/index.php/Coding_Guidelines#CVS_commit_message_form… (for cvs, but i think it can be modified for svn) and https://thomas.apestaart.org/moap/trac regards Vincent Torri PS: i've not subscribed to the boost dev ML. Maybe someone can forward that mail to that list.

1 0

boost array problems.
by chun ping wang 07 Aug '07

07 Aug '07

Hi I have a struct People { const char* fname_; const char* lname_; unsigned int id; } I want to create an array of 3 people. boost::array<People, 3> = { {"Chun", "Wang", 1441}, {"Chia", "Wang", 1443}, {"Ta", "Wang", 1445} }; I get a compile time error too many initializer.

4 5

Re: [Boost-users] [Subversion] Repository back online; please re-checkout
by David Abrahams 06 Aug '07

06 Aug '07

on Mon Aug 06 2007, "Aleksey Gurtovoy" <agurtovoy-AT-meta-comm.com> wrote: > Douglas Gregor wrote: >> We still need help updating regression.py to work with Subversion! > > Done now: http://article.gmane.org/gmane.comp.lib.boost.testing/4578. Thank you! -- Dave Abrahams Boost Consulting http://www.boost-consulting.com The Astoria Seminar ==> http://www.astoriaseminar.com

1 0

QR approximation linear exponantial estimation line fitting
by Alper Emrah Gur 06 Aug '07

06 Aug '07

Is there anyone who can say whether any of the Boost libraries can help me on the subject of this message? Any help will be greatly appreciated.

1 0

serialization build error (and possible fix)
by craigp 06 Aug '07

06 Aug '07

I couldn't build the latest boost from svn with boost build v2 (win32 with msvc 80 sp1, serialization wide-archive compilation/link problems). I've attached a patch which allowed it to build (dunno if this is the right way to fix the problem). It also seems that the following files get deleted after I run bjam... 'svn up' restores these files: Restored: D:\dev\boost\boost.svn\trunk\libs\function_types\build\timestamps\arity_loops Restored: D:\dev\boost\boost.svn\trunk\libs\function_types\build\timestamps\encoding Restored: D:\dev\boost\boost.svn\trunk\libs\function_types\build\timestamps\cc_names HTH, --craig Index: boost/archive/detail/interface_iarchive.hpp =================================================================== --- boost/archive/detail/interface_iarchive.hpp (revision 38471) +++ boost/archive/detail/interface_iarchive.hpp (working copy) @@ -32,7 +32,7 @@ namespace archive { namespace detail { -class BOOST_ARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_iserializer; +class BOOST_ARCHIVE_OR_WARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_iserializer; template<class Archive> class interface_iarchive @@ -51,9 +51,9 @@ } template<class T> - const BOOST_ARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_iserializer * + const BOOST_ARCHIVE_OR_WARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_iserializer * register_type(T * = NULL){ - const BOOST_ARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_iserializer & bpis = + const BOOST_ARCHIVE_OR_WARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_iserializer & bpis = pointer_iserializer<Archive, T>::get_instance(); this->This()->register_basic_serializer(bpis.get_basic_serializer()); return & bpis; Index: boost/archive/detail/interface_oarchive.hpp =================================================================== --- boost/archive/detail/interface_oarchive.hpp (revision 38471) +++ boost/archive/detail/interface_oarchive.hpp (working copy) @@ -32,7 +32,7 @@ namespace archive { namespace detail { -class BOOST_ARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_oserializer; +class BOOST_ARCHIVE_OR_WARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_oserializer; template<class Archive> class interface_oarchive @@ -51,9 +51,9 @@ } template<class T> - const BOOST_ARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_oserializer * + const BOOST_ARCHIVE_OR_WARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_oserializer * register_type(const T * = NULL){ - const BOOST_ARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_oserializer & bpos = + const BOOST_ARCHIVE_OR_WARCHIVE_DECL(BOOST_PP_EMPTY()) basic_pointer_oserializer & bpos = pointer_oserializer<Archive, T>::get_instance(); this->This()->register_basic_serializer(bpos.get_basic_serializer()); return & bpos; Index: libs/serialization/build/Jamfile.v2 =================================================================== --- libs/serialization/build/Jamfile.v2 (revision 38471) +++ libs/serialization/build/Jamfile.v2 (working copy) @@ -44,7 +44,6 @@ basic_xml_archive binary_iarchive binary_oarchive - codecvt_null extended_type_info extended_type_info_no_rtti extended_type_info_typeid @@ -66,6 +65,7 @@ binary_woarchive text_wiarchive text_woarchive + codecvt_null utf8_codecvt_facet xml_wgrammar xml_wiarchive ____________________________________________________________________________________ Pinpoint customers who are looking for what you sell. http://searchmarketing.yahoo.com/

1 0

boost 1.34.1 Foreach conversion to iterators.
by chun ping wang 06 Aug '07

06 Aug '07

Hi i would like to know whats the best way to use BOOST_FOREACH and iterator. Example... BOOST_FOREACH(char c, String str) { first_c = c; // blah.. first iterator = c after condition x. second_c = c; // blah... second iterator = c after condition y. } str2.insert(first_c, second_c). Thanks for any help.

2 3

Serialization issues with 1.34.0 and 1.34.1
by ben.carlyle＠wrsa.com.au 05 Aug '07

05 Aug '07

I tried to raise a bug with trac, but my request was rejected as possible spam. I am currently using the 1.32.0 boost library, but would like to get away from it. One of the main features I am using is boost::serialization. There are some problems with serialization in 1.32.0, in particular that shared_ptr needs to have the "serialization" header included before the real header. The mechanim for handling serialization of shared_ptr is also a problem. Bitset support is also missing. I was hoping to pick up 1.34.0, and have since also made an attempt to use 1.34.1. However, both of these revision appear to have regressions against the 1.32.0 versions. Here is the first bug report I attempted to submit == bug 1: boost/serialization/optional doesn't include necessary headers == The following function refers to version<T>::value without an include of boost/serialization/version.hpp, resulting in user code that won't compile. It is possible to work around this problem by including boost/serialization/version.hpp before including boost/serialization/optional.hpp. I did not require a work-around with boost 1.32.0, but both 1.34.0 and 1.34.1 appear to need the work-around. {{{ template<class Archive, class T> void save( Archive & ar, const boost::optional<T> & t, const unsigned int /*version*/ ) }}} == bug 2: Archive headers missing multiple(?) include files == Here is my test program: #include <boost/archive/binary_iarchive.hpp> #include <boost/archive/binary_oarchive.hpp> #include <boost/archive/xml_iarchive.hpp> #include <boost/archive/xml_oarchive.hpp> int main(void) { return 0; } Here are the first few lines of gcc output: ../boost/boost/boost/archive/basic_binary_iprimitive.hpp:72: error: ISO C++ forbids declaration of ‘scoped_ptr’ with no type ../boost/boost/boost/archive/basic_binary_iprimitive.hpp:72: error: invalid use of ‘::’ ../boost/boost/boost/archive/basic_binary_iprimitive.hpp:72: error: expected ‘;’ before ‘<’ token ../boost/boost/boost/archive/basic_binary_iprimitive.hpp:73: error: ISO C++ forbids declaration of ‘basic_streambuf_locale_saver’ with no type ../boost/boost/boost/archive/basic_binary_iprimitive.hpp:73: error: expected ‘;’ before ‘<’ token ../boost/boost/boost/archive/basic_binary_iprimitive.hpp: In member function ‘void boost::archive::boost::archive::basic_binary_iprimitive<Archive, Elem, Tr> ::load_binary(void*, size_t)’: ../boost/boost/boost/archive/basic_binary_iprimitive.hpp:150: error: ‘throw_exception’ is not a member of ‘boost::archive::boost’ It looks to my untrained eye that there could be several includes missing, or perhaps some circular including going on. == This second bug hits pretty early in my build process, so I would not be surprised if there were additional problems down the line. I am using an ubuntu 7.04 distribution, gcc 4.1.2, etc. Benjamin.

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WIN32_LEAN_AND_MEAN
by KSpam 05 Aug '07

05 Aug '07

My projects need to define WIN32_LEAN_AND_MEAN. Unfortunately, they receive many compilation warnings due to macro redefinition in the following Boost headers (1.34.1). boost/iostreams/detail/system_failure.hpp boost/spirit/iterator/impl/file_iterator.ipp I understand that I can avoid the need to define WIN32_LEAN_AND_MEAN by ensuring that Boost headers are always included prior to <windows.h>. I do not like the idea of include order dependencies, as I am certain that I will come back to bite me down the road. Another option would be to turn the particular warning off; however, I would rather not do this. Would it be prudent to patch the Boost headers to only define WIN32_LEAN_AND_MEAN if it is not already defined? If not, is there another solution that I am overlooking. Thanks, Justin

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Boost.Lambda - using member functions
by Daniel Dilts 05 Aug '07

05 Aug '07

I'm trying to figure out how to use the boost.lambda library, and I'm having some issues, probably stupid ones, but still, issues. In the following code I want to remove all obects from m_devices that only have 1 remaining reference (unique() returns true). Yes, I know that this would be pretty easy, using regular function pointers, and the like, however, I'm trying to learn this library. What am I doing wrong? I would also appreciate any pointers for using boost.lambda Whenever I compile the following code on VS2005 I get the following errors: Warning 1 warning C4512: 'boost::lambda::identity<T>' : assignment operator could not be generated c:\program files (x86)\boost\boost_1_34_0\boost\lambda\detail\lambda_functor_base.hpp 43 Warning 2 warning C4512: 'boost::lambda::lambda_functor<T>' : assignment operator could not be generated c:\program files (x86)\boost\boost_1_34_0\boost\lambda\detail\lambda_functors.hpp 204 Warning 3 warning C4512: 'boost::lambda::identity<T>' : assignment operator could not be generated c:\program files (x86)\boost\boost_1_34_0\boost\lambda\detail\lambda_functor_base.hpp 43 Warning 4 warning C4512: 'boost::lambda::lambda_functor<T>' : assignment operator could not be generated c:\program files (x86)\boost\boost_1_34_0\boost\lambda\detail\lambda_functors.hpp 204 Error 5 error C2451: conditional expression of type 'boost::lambda::detail::member_pointer_caller<RET,A,B>' is illegal c:\program files (x86)\microsoft visual studio 8\vc\include\algorithm 87 Error 6 error C2675: unary '!' : 'boost::lambda::detail::member_pointer_caller<RET,A,B>' does not define this operator or a conversion to a type acceptable to the predefined operator c:\program files (x86)\microsoft visual studio 8\vc\include\algorithm 1240 Error 7 error C2582: 'operator =' function is unavailable in 'std::pair<_Ty1,_Ty2>' c:\program files (x86)\microsoft visual studio 8\vc\include\algorithm 1241 My code for the class I'm having trouble with follows: #pragma once #include <string> #include <map> #include <boost/shared_ptr.hpp> #include "SocketDevice.h" namespace Socket { class SocketFactory { public: SocketFactory(std::string Host, std::string Port); virtual ~SocketFactory(void); protected: std::pair<std::string, std::string> m_dest; boost::shared_ptr<SocketDevice> m_device; static std::map<std::pair<std::string, std::string>, boost::shared_ptr<SocketDevice>> m_devices; private: void RemoveUnreferencedSockets(void); }; }; #include "SocketFactory.h" #include <boost/lambda/lambda.hpp> #include <boost/bind.hpp> Socket::SocketFactory::~SocketFactory(void) { } void Socket::SocketFactory::RemoveUnreferencedSockets(void) { std::remove_if(Socket::SocketFactory::m_devices.begin(), Socket::SocketFactory::m_devices.end(), boost::lambda::_1 ->* &std::pair<std::pair<std::string, std::string>, boost::shared_ptr<SocketDevice> >::second ->* &boost::shared_ptr<SocketDevice>::unique); }

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[1.34.0][iostreams] regex filter seg faults when zero matches found
by Evan Herbst 04 Aug '07

04 Aug '07

The suffix pointer is used in a copy() after only having been initialized to NULL. I attach a patch. My compliments to the chef, otherwise. - Evan

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boost lambda 1.34.1 questions.
by chun ping wang 03 Aug '07

03 Aug '07

HI I have several questions. How do I delete a pointer to a bind type and how do i specify a return type. 2 examples: I want to transform this BOOST_FOREACH code into std::for_each using lambda. typedef std::pair<Foo*, Bar*> FooBar BOOST_FOREACH(FooBar fb , MapFooBar) { delete fb.second; } Foo* f = ... ; BOOST_FOREACH(FooBar fb, MapFooBar) { if (fb.second == o) return fb.first; } 2.) In this case is using BOOST_FOREACH better?

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[Important] Boost Subversion repository is now online
by Douglas Gregor 03 Aug '07

03 Aug '07

Hello all, The Boost Subversion repository is now back online. All of the files in CVS (including their histories) have been imported into the Subversion repository. CVS is still available for anonymous, read- only access for now, but will not be updated. The main Boost development branch is available via anonymous, read- only checkout at: http://svn.boost.org/svn/boost/trunk/ Or for developer read/write access at: https://svn.boost.org/svn/boost/trunk/ Information about accessing the Boost Subversion repository is available at: http://svn.boost.org/trac/boost/wiki/BoostSubversion Please report any problems to me to the main Boost list, and we will try to resolve them as quickly as possible. We still need help porting the regression-testing script over to use Subversion. See Trac ticket #1122: http://svn.boost.org/trac/boost/ticket/1122 Also, there is more documentation that will need to be updated within the Boost tree. - Doug Subversion tip: when you commit a change to Subversion that fixes ticket number NNN, include the text "Fixes #NNN" in your commit log. Trac will automatically close the ticket and cross-reference the commit with the ticket. See, for example, http://svn.boost.org/trac/ boost/changeset/38330

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Re: [Boost-users] boost::regex_match throws exception
by mildaiv＠centrum.cz 03 Aug '07

03 Aug '07

>mildaiv(a)centrum.cz wrote: >> I build boost::regex 1.34 using Borland BDS 2006. >> Simple regular expresions works fine, but I have problem with this >> regular expresion: >> ^[_a-zA-Z0-9-]+(\.[_a-zA-Z0-9-]+)*(a)[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)+$ >> if a try to match it with any string longer then 22 bytes, regex >> throws exception. >> After some investigations i simplified regular expresion to >> ^[10+]*@$ >> and it still throws exception >I can't reproduce with Boost-1.34: please post a complete self contained >test case. Also make sure that those \'s are double escaped if they're >embedded in code: >boost::regex >e("^[_a-zA-Z0-9-]+(\\.[_a-zA-Z0-9-]+)*(a)[a-zA-Z0-9-]+(\\.[a-zA-Z0-9-]+)+$"); This was the problem, everything now works fine. Thanks for your help. >Otherwise the expression does something rather different, and *will* get >pathological and throw an exception. >HTH, John.

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Packed resource files with iostreams & zlib filter
by gyrotech＠freakinabox.com 03 Aug '07

03 Aug '07

Hello all. I am trying to create a wrapper for a set of resources (mixed text, image, etc files) for use in an SDL-based application. I want to use iostreams and keep it as close to C++ as I can, but SDL uses some functions that load data from c-type file pointers or a location in memory using a void* and byte-count. Is it possible to define a method of file access using iostreams and a filter that will then let me create sub-streams of the data inside?? For instance - a zlib-compressed file called 'foobar.gz' that contains 'foo.txt' and 'bar.png'. I want to attach an iostream to foobar.gz then use functions to get the contents in different formats, e.g. stream<my_res_file> compressed_file( "foobar.gz" ); ifstream foo = compressed_file.getasfilestream( "foo.txt" ); // read stuff from foo foo.close(); char* img_data; unsigned long size; compressed_file.getasmembuffer( img_data, &size ); // read img_data and poke around with it delete[] img_data; I know the above is just for illustration, but I can't find any libs that do this sort of work. I am having some real problems now even at the design stage, for instance how to neatly pack multiple files into a single one. My packed-file headers always seem to go wrong and without fixed-length space for files names it gets even more painful :-) If this isn't the right place for this sort of question (I see it's far more conceptual than directly boost-related) then I apologise and will start hitting on some more generic forums and lists ;-) Thanks for your time, GT

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Location of html documention?
by Robert Ramey 03 Aug '07

03 Aug '07

I've downloaded boost on my system and run tests which build the libraries. When I surf the documention on my local hard drive in to "type_traits" I'm redirected to the www.boost.org How do I get the html documentation on my hard drive. Perhaps it is produced by the normal install process - which I confess I didn't do - as running the tests builds the libraries I need. I looked for it there but I didn't see it. Robert Ramey

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[Boost.Thread] self deadlocking issue
by Cheng Lian 03 Aug '07

03 Aug '07

Hi, all I was debugging a buggy program which could be simplified as below: #include <boost/thread.hpp> using namespace boost; mutex m; void f() { mutex::scoped_lock lock( m ); } int main() { mutex::scoped_lock lock( m ); f(); return 0; } I think this would definitely self deadlock and the program should be waiting forever. And my Debian Linux box proved that true. But on my XP (with SP2) box, the program didn't dead lock and everything pass through! Seems that on Win32 platform, the mutex is recursive? I checked the code and only CRITICAL_SECTION related is found around the lock/unlock lines. But I think CRITICAL_SECTION itself is not recursive. Then why? Thanks for response. Cheers Cheng

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