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How to use interprocess communication to load the data into map
by manish4gupta 17 Sep '09

17 Sep '09

Hi, I am using boost interprocess library for loading the data into map <string, string> . And reading the same map with another program.I am benchmarking the code given on the following lilnk. http://www.boost.org/doc/libs/1_38_0/doc/html/interproc/quick_guide.html#in… #include <boost/interprocess/managed_shared_memory.hpp> #include <boost/interprocess/containers/map.hpp> #include <boost/interprocess/allocators/allocator.hpp> #include <functional> #include <utility> int main () { using namespace boost::interprocess; //Shared memory front-end that is able to construct objects //associated with a c-string. Erase previous shared memory with the name //to be used and create the memory segment at the specified address and initialize resources shared_memory_object::remove("MySharedMemory"); try{ managed_shared_memory segment (create_only ,"MySharedMemory" //segment name ,65536); //segment size in bytes //Note that map<Key, MappedType>'s value_type is std::pair<const Key, MappedType>, //so the allocator must allocate that pair. typedef int KeyType; typedef float MappedType; typedef std::pair<const int, float> ValueType; //Alias an STL compatible allocator of for the map. //This allocator will allow to place containers //in managed shared memory segments typedef allocator<ValueType, managed_shared_memory::segment_manager> ShmemAllocator; //Alias a map of ints that uses the previous STL-like allocator. //Note that the third parameter argument is the ordering function //of the map, just like with std::map, used to compare the keys. typedef map<KeyType, MappedType, std::less<KeyType>, ShmemAllocator> MyMap; //Initialize the shared memory STL-compatible allocator ShmemAllocator alloc_inst (segment.get_segment_manager()); //Construct a shared memory map. //Note that the first parameter is the comparison function, //and the second one the allocator. //This the same signature as std::map's constructor taking an allocator MyMap *mymap = segment.construct<MyMap>("MyMap") //object name (std::less<int>() //first ctor parameter ,alloc_inst); //second ctor parameter //Insert data in the map for(int i = 0; i < 100; ++i){ mymap->insert(std::pair<const int, float>(i, (float)i)); } } catch(...){ shared_memory_object::remove("MySharedMemory"); throw; } shared_memory_object::remove("MySharedMemory"); return 0; } but getting the following errors. manish@user-desktop:~/Desktop$ g++ memorymap.cpp /tmp/ccmOQCB8.o: In function `boost::interprocess::shared_memory_object::priv_open_or_create(boost::interprocess::detail::create_enum_t, char const*, boost::interprocess::mode_t)': memorymap.cpp:(.text._ZN5boost12interprocess20shared_memory_object19priv_open_or_createENS0_6detail13create_enum_tEPKcNS0_6mode_tE[boost::interprocess::shared_memory_object::priv_open_or_create(boost::interprocess::detail::create_enum_t, char const*, boost::interprocess::mode_t)]+0x163): undefined reference to `shm_open' /tmp/ccmOQCB8.o: In function `boost::interprocess::detail::mutexattr_wrapper::mutexattr_wrapper(bool)': memorymap.cpp:(.text._ZN5boost12interprocess6detail17mutexattr_wrapperC1Eb[boost::interprocess::detail::mutexattr_wrapper::mutexattr_wrapper(bool)]+0x14): undefined reference to `pthread_mutexattr_init' memorymap.cpp:(.text._ZN5boost12interprocess6detail17mutexattr_wrapperC1Eb[boost::interprocess::detail::mutexattr_wrapper::mutexattr_wrapper(bool)]+0x2b): undefined reference to `pthread_mutexattr_setpshared' memorymap.cpp:(.text._ZN5boost12interprocess6detail17mutexattr_wrapperC1Eb[boost::interprocess::detail::mutexattr_wrapper::mutexattr_wrapper(bool)]+0x4d): undefined reference to `pthread_mutexattr_settype' /tmp/ccmOQCB8.o: In function `boost::interprocess::detail::mutexattr_wrapper::~mutexattr_wrapper()': memorymap.cpp:(.text._ZN5boost12interprocess6detail17mutexattr_wrapperD1Ev[boost::interprocess::detail::mutexattr_wrapper::~mutexattr_wrapper()]+0xd): undefined reference to `pthread_mutexattr_destroy' /tmp/ccmOQCB8.o: In function `boost::interprocess::shared_memory_object::remove(char const*)': memorymap.cpp:(.text._ZN5boost12interprocess20shared_memory_object6removeEPKc[boost::interprocess::shared_memory_object::remove(char const*)]+0x33): undefined reference to `shm_unlink' collect2: ld returned 1 exit stats. What is the reason for this pblm? Thanks in advance. Regards Manish -- View this message in context: http://www.nabble.com/How-to-use-interprocess-communication-to-load-the-dat… Sent from the Boost - Users mailing list archive at Nabble.com.

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boost::Interprocess sharing objects using virtual inheritance
by Martin Kaiser 16 Sep '09

16 Sep '09

hi, I am currently developing an API for PCI devices. Multiple processes should be able to use the API simultaniously, but there may be only one instance of the API and all processes have to use that same instance. So I decided to use a shared memory with a vector containing all instances of the PCI device Objects. The Problem is that my PCI Device Object uses virtual inheritance and the doc of boost::interprocess says that it isn't possible (see below). Now I am wondering if it's possible to store an offset_ptr or a kind of Ownership smart pointer in that vector pointing to my virtual inherited Device Object in a Managed Memory Segment (not memory mapped region!). Can anybode give me a hint on this? Thank in regards Martin from http://www.boost.org/doc/libs/1_39_0/doc/html/interprocess/sharedmemorybetw… : Virtuality forbidden The virtual table pointer and the virtual table are in the address space of the process that constructs the object, so if we place a class with a virtual function or virtual base class, the virtual pointer placed in shared memory will be invalid for other processes and they will crash. This problem is very difficult to solve, since each process needs a different virtual table pointer and the object that contains that pointer is shared across many processes. Even if we map the mapped region in the same address in every process, the virtual table can be in a different address in every process. To enable virtual functions for objects shared between processes, deep compiler changes are needed and virtual functions would suffer a performance hit. That's why Boost.Interprocess does not have any plan to support virtual function and virtual inheritance in mapped regions shared between processes.

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cannot pass objects of non-POD type ‘class boost::detail::shared_count’ through ‘...’; call will abort at runtime
by Dave Steffen 16 Sep '09

16 Sep '09

Hi Folks Just tried to compile my project with GCC 4.3 and Boost 1.40. (It compiles and works just fine with Boost 1.38.) As part of a home-built thread-locking shared pointer thing, we have this code: /// Constructor from pointer to complete type template<class Y> explicit shared_locking_ptr( Y * p ): px( p ), pn( p ) // Y must be complete { boost::detail::sp_enable_shared_from_this( pn, p, p ); } which now produces this result: ../util/thread/shared_locking_ptr.hpp:57:9: warning: cannot pass objects of non-POD type ‘class boost::detail::shared_count’ through ‘...’; call will abort at runtime In Boost 1.38, the relevent code in shared_ptr.hpp was this AFAICT: #ifdef _MANAGED [ ... ] #else // _MANAGED [...] inline void sp_enable_shared_from_this( shared_count const & /*pn*/, ... ) { } #endif // _MANAGED In 1.40, it's been changed to #ifdef _MANAGED [...] #else // _MANAGED inline void sp_enable_shared_from_this( ... ) { } #endif // _MANAGED Does anyone know why the change? Has anybody else seen this problem? It seems to me that GCC is correct, and that although it's an empty function so it doesn't matter anyway, the earlier version is preferable. Alternately, does anyone know of a way to silence GCC's warning? -- Dave Steffen, Ph.D - Software Engineer Numerica Corporation (www.numerica.us <http://www.numerica.us/> ) 4850 Hahns Peak Drive, Suite 200 Loveland, Colorado 80538 main (970) 461-2000 x 227 direct (970) 612-2327 fax (970) 461-2004 Email: dave.steffen(a)numerica.us

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Using rs232 libraries with Wince 5.0
by Matthew Dobrzenski 16 Sep '09

16 Sep '09

Hello, I am attempting to use the boost rs232 libraries for a wince based program I am writing. To use the serial port libraries I am including the following files: #include <boost/asio.hpp> #include <boost/asio/serial_port.hpp> Upon compilation I get the following error: fatal error C1083: Cannot open include file: 'cerrno': No such file or directory This is failing at the include of "#include <cerrno>" in the cerrno.hpp file. My compiler is visual studios 2005 (version: 8.0.50727.42), release mode, platform windows mobile 5.0 pocket pc. Thanks in advance for any help that you can offer. Matt -- Matthew J Dobrzenski Electrical Engineer/Computer Engineer

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[mpl] template parameters and mpl::if_/mpl::eval_if
by Edward Diener 16 Sep '09

16 Sep '09

I know I can try this out but I will ask here anyway just to make sure my test is not being incorrectly done. Can mpl::if_/mpl::eval_if be used to pick the type for which a default template parameter is set based on some metaprogramming boolean test of a previous template parameter type ? I know that C++ allows a template parameter default to be set based on a previous template parameter, but I don't know if mpl::if_/mpl::eval_if can be used in this context.

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gdb crash when loading lib with (big) Spirit grammar
by Christoph Duelli 16 Sep '09

16 Sep '09

I have a quite big Spirit (1.38) grammar inside a lib. (Running OpenSuSE 11.1 Linux, gcc 4.3.2, gdb 6.8.50; both 32 bit and 64 bit.) When trying to debug a programm linked against this lib, gdb crashes - when trying to read the lib's symbol table. (gdb) at 19281 Attaching to process 19281 Reading symbols from ....i_mepl_debug...done. Reading symbols from ....libMEPL_debug.so.6... Segmentation fault (core dumped) (Note that this is not my program crashing but gdb. And no, the program is not buggy, has not corrupted the stack or anything like that ;-) Debugging does work on older openSuSE (or SLES) releases, e.g. on openSuSE 10.3., SLES 10, SLES9. I have build and tried the latest gdb release, but it shows the same behaviour as the one part of the release. A stack trace of the gdb core showed that the crash seems to have occured in cplus_demangle_v3. I have searched google and found some postings that indicate the issue might stem from too long symbols being generated for Spirit (or Xpressive) constructs. (A quick glance on nm output shows, there are some symbols of some 1000 characters in size. Might be even longer ones.) Has anyone else stumbled upon this and maybe found out what the culprit is? A bug in gcc? gdb? name (de)mangling? Any ideas? Best regards Christoph

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Re: [Boost-users] building boost 1_33_1 now 1_37_0
by Dan Smithers 16 Sep '09

16 Sep '09

>> >> How do I change the includes in jam? > > Sorry, I don't understand the above. Boost.Build does not pass any > "intel includes" nor any "gcc 2.95 includes". Can you provide the commands > lines and errors in question and explain how exactly the command lines > should be altered. I've now found that as long as I make sure that gcc 3.4.3 is ahead of 2.95 in the search path I can get past the first hurdle. The command line that comes out is "icpc" -c -xc++ -O3 -Ob2 -w1 -fPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_MATH_TR1_DYN_LINK -DNDEBUG -I"." -c -o "bin.v2/libs/math/build/intel-linux-release/threading-multi/hypot.o" "libs/math/build/../src/tr1/hypot.cpp" /usr/lib/pthread.h(163): error: expected a ")" extern int pthread_create(pthread_2 *__restrict __thread, ^ I have written a short test program that includes pthread.h and that compiles. thanks dan

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[Asio] Why does Boost Asio only allow 64 buffers to be sent/recei ved using scatter/gather?
by Stephens Patrick 16 Sep '09

16 Sep '09

Hi all, Apologies if this question should be directed at an Asio-specific list but I could not see one. I am curious why the Boost Asio library specifies a maximum of 64 buffers can be used for scatter/gather operations? I would like to gain a better understanding as to why this value was used. The documentation (http://www.boost.org/doc/libs/1_40_0/doc/html/boost_asio/overview/implement ation.html), and the code backs it up, seems to specify that the maximum allowed will be 'min(64, IOV_MAX)' for linux implementations. Was this value (64) chosen for some particular reason? What would the consequences be of using IOV_MAX if it was greater than 64? I see that the Windows NT, 2000, XP, 2003 and Vista implementation also has a limit of 64 so is this something limited by the OS or to keep it consistent across all the Asio implementations? I had a look around to see if there was a restriction under Windows but the only documentation I could find (http://msdn.microsoft.com/en-us/library/ms742203%28VS.85%29.aspx) mentions that it is restricted to a value of 16 under Windows 95, 98 and ME, which does tally with what the Asio documentation states in the link above. Thanks for any help, Pat. This email, including any attachment, is a confidential communication intended solely for the use of the individual or entity to whom it is addressed. It contains information which is private and may be proprietary or covered by legal professional privilege. If you have received this email in error, please notify the sender upon receipt, and immediately delete it from your system. Anything contained in this email that is not connected with the businesses of this company is neither endorsed by nor is the liability of this company. Whilst we have taken reasonable precautions to ensure that any attachment to this email has been swept for viruses, we cannot accept liability for any damage sustained as a result of software viruses, and would advise that you carry out your own virus checks before opening any attachment.

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[serialization] can load_construct_data() access private members?
by Igor R 16 Sep '09

16 Sep '09

Hello, How to grant load_construct_data() the permission to access private members of the serializable class? friend class ::boost::serialization::access; // doesn't help template<class Archive> friend void ::boost::serialization::load_construct_data(Archive &ar, MyObj *t, const unsigned int file_version); // doesn't compile with MSVC9.0SP1 One of my classes can be created with a static function only: class Foo { public: shared_ptr<Foo> create(Arg a) { shared_ptr<Foo> self(new Foo(a)); self->init(); return self; } private: Foo(Arg a); void init(); }; I try to simulate this behavior in load_construct_data() function. Thanks.

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[Date Time] Redundant warnings with w4 on MSVC
by Василий Старостин 16 Sep '09

16 Sep '09

Hi! When I try to compile my program by MSVC 9 using w4 option (maximum warnings), I got several warnings in this library headers. It prevents me from using w4 :(. How can I use Boost Date-Time library with MSVC w4 option and don't get lots of warnings? WBR, Vasily

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Re: [Boost-users] Boost-users Digest, Vol 2119, Issue 2
by N Z 16 Sep '09

16 Sep '09

Thank you Volodya, adding /MD works. Neil > Message: 2 > Date: Tue, 15 Sep 2009 09:37:27 +0400 > From: Vladimir Prus <vladimir(a)codesourcery.com> > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] link error on boost example using binary > library > Message-ID: <h8n96i$dhd$1(a)ger.gmane.org> > Content-Type: text/plain; charset=utf-8 > > N Z wrote: > >> Hi there, >> I am a beginner using boost. I am installing boost 1.40 on >> windows XP with sp3 and Visual Studio Standard 2008. I followed the >> "Getting Started on Windows"? section 5.2???"Or, Simplified Build From >> Source. to build my binaries". i.e. >> >> bootstrap >> .\bjam >> >> I then tried to run the example in section 6:Link Your Program to a >> Boost Library. >> I got expected results when link from the IDE, however, I can't link >> under command prompt, here's the output I got when compiling: >> ****************************************************************************** >> C:\Documents and Settings\Administrator\My Documents\Visual Studio >> 2008\Projects\boostBinaryLibExamp>cl /EHsc /I "c:\Program >> Files\boost\boost_1_40_0" boostBinaryLibExamp\boostBinaryLibExamp.cpp >> /link "c:\Program >> Files\boost\boost_1_40_0\stage\lib\libboost_regex-vc90-mt-1_40.lib" >> Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 15.00.21022.08 for 80x86 >> Copyright (C) Microsoft Corporation. ?All rights reserved. >> boostBinaryLibExamp.cpp >> Microsoft (R) Incremental Linker Version 9.00.21022.08 >> Copyright (C) Microsoft Corporation. ?All rights reserved. >> /out:boostBinaryLibExamp.exe >> "c:\Program Files\boost\boost_1_40_0\stage\lib\libboost_regex-vc90-mt-1_40.lib" >> boostBinaryLibExamp.obj >> LINK : fatal error LNK1104: cannot open file 'libboost_regex-vc90-mt-s-1_40.lib' >> ****************************************************************************** >> >> I searched in the lib directory, there's no such file there. But why I >> can link from IDE but not in command prompt? > > Because IDE uses dynamic runtime by default. Seems like command line compiler > wants static runtime. You should probably pass /MD to the compiler. Also, > make sure "c:\Program Files\boost\boost_1_40_0\stage\lib\" is in libraries > search patch. (/LIBPATH) > > - Volodya >

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[units] - overriding output
by Noah Roberts 15 Sep '09

15 Sep '09

What is the correct way to override the << op for a unit so that it say prints "Pa" instead of "m^-1 kg s^-2"? I tried this and no worky: #include <boost/units/io.hpp> namespace boost { namespace units { template<> inline std::string name_string< boost::units::pressure_dimension, boost::units::si::system >(const boost::units::si::pressure&) { return "Pa"; } }} // boost::units Also, I note that the operator << in io.hpp has a comment saying "INTERNAL USE ONLY". How would you suggest then that users of the library provide for stream output without running afoul of this implementation we're not meant to use?

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[serialization] how to serialize boost::function
by Igor R 15 Sep '09

15 Sep '09

Hello, Is it possible to serialize the following class: struct foo { void f1(int a) {} void f2(const std::string& s) {} void init() { using boost::bind; functors_.push_back(bind(&foo::f1, this, 1)); functors_.push_back(bind(&foo::f2, this, "test")); } std::vector<boost::function<void(void)> > functors_; }; That is, I'd like save the functors, in order to run them later, when the object is loaded from the archive. A straightforward attempt fails: struct foo { //...... friend class boost::serialization::access; template<class Archive> void serialize(Archive &ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(functors_); } }; 1>d:\dev\servision\projects\windows\thirdparty\boost\boost\serialization\access.hpp(109) : error C2039: 'serialize' : is not a member of 'boost::function<Signature>'

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shared_ptr<T> callback
by Vjekoslav Brajkovic 15 Sep '09

15 Sep '09

Hello! :) I'm writing a write-through cache unit which returns const shared_ptr<T>. After the data has been modified and once share_ptr goes out of scope, I would like the shared_ptr destructor to call a handler which would commit the modified value to some other location -- a DHT for instance. Is there a way to supply a callback function to shared_ptr destructor? Any help would be greatly appreciated. Please let me know if the question is too ambiguous. Thanks! V

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Re: [Boost-users] lexical problem
by Anders Dalvander 15 Sep '09

15 Sep '09

pedro chaparro wrote: > in the ouput i have this : 5050?? > > the first "50" i write with > std::cout.write(buf.data(),len); > > and the second "50" plus those stange characters > > std::string datos=buf.data(); > printf("%s \n",datos); > > i suppose that those characters means that are not null terminated. right? > So how can i only take the "50" without the other characters? > > thanks > std::string does not work well with varargs, use std::string::c_str member function to convert it to a null-terminated string: printf("%s \n",datos.c_str()); Regards, Anders Dalvander

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Re: [Boost-users] lexical problem
by cliffg＠codewrangler.net 15 Sep '09

15 Sep '09

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Get results of graph cut?
by David Doria 15 Sep '09

15 Sep '09

If I do this: double flow = kolmogorov_max_flow(g, SourceNode, SinkNode); I get the value of the max flow, but how do I tell which nodes of g belong to the "source side" of the graph and which nodes belong to the "sink side"? (thinking of it as a min cut rather than a max flow problem) Also, is it possible to tell the max flow algorithm to use multiple sources/sinks? Thanks, David

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[Sigal] Combiner sample code outputs nothing
by Boost lzw 15 Sep '09

15 Sep '09

Hi there, I got nothing outputted from the following sample code on page 360 to 362 of the book "Beyond the C++ Standard". Did I missed something? Thanks in advance. Robert ============== #include <iostream> #include "boost/signals.hpp" // boost book, pp. 360 - 362 bool step0() { std::cout << "Step 0 is OK.\n"; return true; }; bool step1() { std::cout << "Step 1 is not OK. This won't do at all. \n"; return false; }; bool step2() { std::cout << "Step 2 is OK. \n"; return true; }; // we need this one as Combiner class stop_on_failure { public: typedef bool result_type; template<typename InputIterator> bool operator()(InputIterator begin, InputIterator end) const { while (begin != end); { if (!*begin) return false; ++begin; } return true; } }; int main() { boost::signal<bool (), stop_on_failure> sig; sig.connect(0, &step0); sig.connect(1, &step1); sig.connect(2, &step2); bool ok = sig(); if (ok) std::cout << "All system tests clear. \n"; else std::cout << "At least one test failed. Aborting. \n"; return 0; } ==============

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Re: [Boost-users] building boost 1_33_1 now 1_37_0
by Dan Smithers 15 Sep '09

15 Sep '09

Message: 6 Date: Tue, 15 Sep 2009 14:44:40 +0400 From: Vladimir Prus <vladimir(a)codesourcery.com> To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] Boost-users Digest, Vol 2115, Issue 4 Message-ID: <h8nr6o$1od$1(a)ger.gmane.org> Content-Type: text/plain; charset=us-ascii Dan Smithers wrote: >> >> Date: Fri, 11 Sep 2009 20:06:17 +0400 >> >> From: Vladimir Prus <vladimir(a)codesourcery.com> >> >> To: boost-users(a)lists.boost.org >> >> Subject: Re: [Boost-users] building boost 1_33_1 >> >> Message-ID: <h8dshm$bce$2(a)ger.gmane.org> >> >> Content-Type: text/plain; charset=us-ascii >> >> >> >> Dan Smithers wrote: >> >> >>> >>> I need to recompile boost 1_33_1 with the intel compiler icc 9.0 >>> >>> >>> >>> The jamfiles are trying to use 8 in /opt (which doesn't actually exist). >>> >>> >>> >>> Please can someone point me in the right direction to do this. > > Thanks for the reply. > > > > I have done some more things, and decided to try the same with boost > > 1.37 - the next version that I have been using. > > >>> >>> >>> >>> I am using >>> >>> >>> >>> ./configure CXX=icc --prefix=/vol/build --with-toolset=intel-linux >>> >>> --with-bjam=/vol/build/boost-jam-3.1.17/bin.linuxx86/bjam >> >> >> >> 1.33.1 is very old; and worse, it was using older version of Boost.Build. >> >> Therefore, I'd recommend just hacking your way around in tools/build/v2/ >> >> intel-tools.jam, or however the file is called. > > > > My problem now seems to be in the actual compilation: It tries to build > > in workarounds for gcc 2.95 and complains with about wrongly named > > header files. If this results in compilation errors, you should see the compile command after the errors. > > > > Possibly the problem is because I don't understand enough Jam to work > > out what commands are actually being run. Also, the "-d+2" option will print all commands that are run, not just those that failed. Thanks for that hint - I've edited the makefile to call bjam -d+2 so I can see that it is the call to icpc that is failing. It looks as if the intel includes are not being used and the default gcc 2.95 ones are put in instead. How do I change the includes in jam?

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CentOS 4.7 and boost 1.35+
by Timothy Chan 15 Sep '09

15 Sep '09

Hi all, I have a newbie question here. I am running CentOS4.7 and have Boost 1.32 installed. I need to upgrade to at least 1.35 but it seems that yum only brings up version 1.32 or 1.33 versions. Does anybody have any recommendations on how to upgrade? If i simply download 1.40 from the website, are there any CentOS specific directions that anybody can give? Thanks for any help I can get. -Tim

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[interprocess] theoretical questions about interprocess conditions
by Kishalay Kundu 15 Sep '09

15 Sep '09

Hi, I am designing a multithreaded application that uses interprocess_condition variables as part of my synchronization process. I have some questions about the internal workings of interprocess_condition and would be grateful if someone provides their feedback on my general design. My application is designed such that there are several threads (say A, B, C & D) that all access different chunks of data asynchronously based on individual conditions (say cA, cB, cC, cD). However, each chunk needs to be accessed in sequence. So, for a single chunk of data, an example would be as following: 1. A waits on condition cA, executes its code, then issues notification for condition cB. 2. B waits on condition cB, executes its code, then issues notification for condition cC. 2. C waits on condition cC, executes its code, then issues notification for condition cD. 2. D waits on condition cD, executes its code, then issues notification for condition cA. >From the examples on the web-site, it looks like, one can use scoped_lock and interprocess_condition in the following manner: void thread_func(...) { // example code for thread B scoped_lock < boost::interprocess::interprocess_mutex > lock( my_mutex ); cB.wait( lock ); // work code // notify next thread cC.notify_all( ); } In this case, thread B will get into the my_mutex queue and wait for thread A to notify when and the condition cB is fulfilled and then take ownership of the mutex. Question 1: If thread B locks my_mutex after thread A has already issued the cB notification, will B be able to recognize this and take ownership of the mutex? My design is such that no other thread is actually waiting for cB. If B does not recognize the condition, it will result in a stall of the whole pipeline (since it won't issue notification on cC). Is this a correct assessment? Question 2: I give below an example of the code I'm using. I'd like to know if this will generate the behavior I'm looking for. The design is based on the fact that different threads perform different operations on the data and they do these operations in a particular order (eg. A, then B, then C, then D). I divide the data up into chunks so that every thread is working on some part of the data instead of being held up. I use the try_to_lock stuff so that if a thread doesn't get an immediate lock, it just moves on to the next chunk of data and sees if it can work on that. Is this an efficient way to make use of my resources. // example function void thread_func( ... ) { scoped_lock < boost::interprocess::interprocess_mutex > my_lock( my_mutex, try_to_lock ); if( my_lock ){ cB. wait( my_lock ); // do some work cC.notify_all( ); } } Thanks in advance. I truly appreciate the help. Kish

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[random] Poisson generator
by Rupert Mazzucco 15 Sep '09

15 Sep '09

Hello, is there a reason the Poisson generator is no longer mentioned in the documentation for 1.40.0? It seems to be there and working. Cheers -- Rupert Mazzucco <mazzucco(a)iiasa.ac.at> Research Scholar, Evolution and Ecology Program IIASA - Institute for Applied Systems Analysis Schlossplatz 1, 2361 Laxenburg, Austria Phone: +43 2236 807 522 Fax: +43 2236 713 13

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[spirit] [test] Double deletion with auto-registered test suite?
by Alastair Rankine 15 Sep '09

15 Sep '09

My very simple test app (complete code below) is getting a possible double-deletion error, and it seems to have something to do with Boost Test auto-registration. Here's the error: % ./spirit2 Running 2 test cases... *** No errors detected spirit2(55443) malloc: *** error for object 0x3000101700a10: pointer being freed was not allocated *** set a breakpoint in malloc_error_break to debug zsh: abort ./spirit2 Here's the stack trace: (gdb) bt #0 0x00007fff88021b91 in malloc_error_break () #1 0x00007fff87f4b083 in free () #2 0x000000010006c3ac in boost::unit_test::framework_impl::clear (this=0x1000deec0) at framework.ipp:133 #3 0x000000010006c4aa in boost::unit_test::framework_impl::~framework_impl (this=0x1000deec0) at framework.ipp:122 #4 0x000000010006da1e in __tcf_1 () at framework.ipp:225 #5 0x00007fff87f57274 in __cxa_finalize () #6 0x00007fff87f5718c in exit () #7 0x000000010000b7bb in start () at unit_test_parameters.ipp:172 The code is compiled on MacOS X 10.6.1 with the supplied gcc 4.2 compiler. Using Boost 1.40.0 as installed by MacPorts. The Spirit guys reckon there's no heap allocation at all within their library, so that kindof points the finger at Boost Test. Also the problem goes away if you comment out one of the test cases, or remove the BOOST_AUTO_TEST_SUITE calls. Unless I'm doing something obviously wrong...? Help appreciated. #define BOOST_TEST_MODULE spirit test #include <boost/test/included/unit_test.hpp> #include <boost/spirit/include/qi.hpp> namespace qi = boost::spirit::qi; template <typename Iterator> struct MyGrammar : public qi::grammar<Iterator> { MyGrammar() : MyGrammar::base_type(sp) { using boost::spirit::char_; sp = char_(' '); } qi::rule<Iterator> sp; }; BOOST_AUTO_TEST_SUITE(SpiritTest) BOOST_AUTO_TEST_CASE(Test1) { MyGrammar<std::string::const_iterator> parser; } BOOST_AUTO_TEST_CASE(Test2) { MyGrammar<std::string::const_iterator> parser; } BOOST_AUTO_TEST_SUITE_END()

1 0

Re: [Boost-users] Boost-users Digest, Vol 2115, Issue 4
by Dan Smithers 15 Sep '09

15 Sep '09

> Date: Fri, 11 Sep 2009 20:06:17 +0400 > From: Vladimir Prus <vladimir(a)codesourcery.com> > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] building boost 1_33_1 > Message-ID: <h8dshm$bce$2(a)ger.gmane.org> > Content-Type: text/plain; charset=us-ascii > > Dan Smithers wrote: > >> I need to recompile boost 1_33_1 with the intel compiler icc 9.0 >> >> The jamfiles are trying to use 8 in /opt (which doesn't actually exist). >> >> Please can someone point me in the right direction to do this. Thanks for the reply. I have done some more things, and decided to try the same with boost 1.37 - the next version that I have been using. >> >> I am using >> >> ./configure CXX=icc --prefix=/vol/build --with-toolset=intel-linux >> --with-bjam=/vol/build/boost-jam-3.1.17/bin.linuxx86/bjam > > 1.33.1 is very old; and worse, it was using older version of Boost.Build. > Therefore, I'd recommend just hacking your way around in tools/build/v2/ > intel-tools.jam, or however the file is called. My problem now seems to be in the actual compilation: It tries to build in workarounds for gcc 2.95 and complains with about wrongly named header files. Possibly the problem is because I don't understand enough Jam to work out what commands are actually being run. thanks dan

2 1

link error on boost example using binary library
by N Z 15 Sep '09

15 Sep '09

Hi there, I am a beginner using boost. I am installing boost 1.40 on windows XP with sp3 and Visual Studio Standard 2008. I followed the "Getting Started on Windows" section 5.2 "Or, Simplified Build From Source. to build my binaries". i.e. bootstrap .\bjam I then tried to run the example in section 6:Link Your Program to a Boost Library. I got expected results when link from the IDE, however, I can't link under command prompt, here's the output I got when compiling: ****************************************************************************** C:\Documents and Settings\Administrator\My Documents\Visual Studio 2008\Projects\boostBinaryLibExamp>cl /EHsc /I "c:\Program Files\boost\boost_1_40_0" boostBinaryLibExamp\boostBinaryLibExamp.cpp /link "c:\Program Files\boost\boost_1_40_0\stage\lib\libboost_regex-vc90-mt-1_40.lib" Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 15.00.21022.08 for 80x86 Copyright (C) Microsoft Corporation. All rights reserved. boostBinaryLibExamp.cpp Microsoft (R) Incremental Linker Version 9.00.21022.08 Copyright (C) Microsoft Corporation. All rights reserved. /out:boostBinaryLibExamp.exe "c:\Program Files\boost\boost_1_40_0\stage\lib\libboost_regex-vc90-mt-1_40.lib" boostBinaryLibExamp.obj LINK : fatal error LNK1104: cannot open file 'libboost_regex-vc90-mt-s-1_40.lib' ****************************************************************************** I searched in the lib directory, there's no such file there. But why I can link from IDE but not in command prompt? btw, the boostPro installer only has version 1.39, right? I want to use 1.40. Thanks, Neil

2 1

why is this bzip2 boost code so slow?
by ChristinaDRS 14 Sep '09

14 Sep '09

Hello, This code with bzip2 takes 185 seconds to do 10000 iterations of compressing and uncompressing. This seems way too high. When I replace the bzip2 code with zlib code it take roughly 7 seconds. Anyone know what might be wrong? #include <iostream> #include <sstream> #include <boost/assign/list_of.hpp> #include <boost/date_time/posix_time/posix_time.hpp> #include <boost/foreach.hpp> #include <boost/format.hpp> #include <boost/lexical_cast.hpp> #include <boost/numeric/conversion/cast.hpp> #include <boost/iostreams/copy.hpp> #include <boost/iostreams/device/back_inserter.hpp> #include <boost/iostreams/filter/bzip2.hpp> #include <boost/iostreams/filter/zlib.hpp> #include <boost/iostreams/filtering_stream.hpp> using namespace std; typedef boost::posix_time::ptime TimeType; TimeType current_time() { return boost::posix_time::microsec_clock::local_time(); } double elapsed_seconds(const TimeType& start_time) { static const double MSEC_PER_SEC = 1000.0; TimeType end_time = current_time(); boost::posix_time::time_duration elapsed = end_time - start_time; return boost::numeric_cast<double>(elapsed.total_milliseconds()) / MSEC_PER_SEC; } string decompress(const string& data) { boost::iostreams::filtering_streambuf<boost::iostreams::input> in; in.push(boost::iostreams::bzip2_decompressor()); in.push(boost::make_iterator_range(data)); string decompressed; boost::iostreams::copy(in, boost::iostreams::back_inserter(decompressed)); return decompressed; } int main() { TimeType start_time = current_time(); string compressed, received_data; boost::iostreams::filtering_streambuf<boost::iostreams::output> out, in; const string send_data = "boo! how are you?"; for(int i = 0; i < 10000; ++i) { //compress out.push(boost::iostreams::bzip2_compressor()); out.push(boost::iostreams::back_inserter(compressed)); boost::iostreams::copy(boost::make_iterator_range(send_data), out); const string compressed1=compressed; //decompress received_data = decompress(compressed); } cout << "time elapsed: " << elapsed_seconds(start_time) << endl; } -- View this message in context: http://www.nabble.com/why-is-this-bzip2-boost-code-so-slow--tp25442062p2544… Sent from the Boost - Users mailing list archive at Nabble.com.

2 1

[spirit] benchmarks/qi benchmarks valid?
by Daniel Mierswa 14 Sep '09

14 Sep '09

Hey list, I was merely wondering if what I'm doing is right or if I fail at basic benchmarking: impulze@istari ~/dev/repositories/boost.svn/libs/spirit/benchmarks/qi $ g++ -O3 int_parser.cpp -I../../../../ -lrt && ./a.out /////////////////////////////////////////////////////////////////////////// Numbers to test: 1 digit number:-5 2 digit number:-54 3 digit number:541 4 digit number:-9604 5 digit number:-50733 6 digit number:-162974 7 digit number:-3133813 8 digit number:39950230 9 digit number:298344332 /////////////////////////////////////////////////////////////////////////// atoi_test: 5.0041852930 [s] {checksum: 13f6bf40} strtol_test: 5.4193627260 [s] {checksum: 13f6bf40} spirit_int_test: 2.2137115780 [s] {checksum: 13f6bf40} impulze@istari ~/dev/repositories/boost.svn/libs/spirit/benchmarks/qi $ g++ -O0 int_parser.cpp -I../../../../ -lrt && ./a.out /////////////////////////////////////////////////////////////////////////// Numbers to test: 1 digit number:5 2 digit number:-55 3 digit number:-978 4 digit number:2835 5 digit number:-78343 6 digit number:354806 7 digit number:9413631 8 digit number:-10824620 9 digit number:-369204759 /////////////////////////////////////////////////////////////////////////// atoi_test: 0.5902040060 [s] {checksum: e9ed193a} strtol_test: 0.6001010490 [s] {checksum: e9ed193a} spirit_int_test: 3.6562933090 [s] {checksum: e9ed193a} According to this, the optimized binary is 10 times slower wrt to the atoi/strtol implementation. I find that somehow quite hard to believe, is my toolchain broken, the testsuite or is it really true? The level of optimization doesn't matter btw, I get similar results with -O[,1,2] Any ideas are welcome. -- Mierswa, Daniel If you still don't like it, that's ok: that's why I'm boss. I simply know better than you do. --- Linus Torvalds, comp.os.linux.advocacy, 1996/07/22

4 7

Boost.Signals2 - tracking an object managed with tr1::shared_ptr
by Monteleone, Nathan 14 Sep '09

14 Sep '09

Is it possible to use slot::track with a tr1::shared_ptr instead of a boost::shared_ptr? For example: std::tr1::shared_ptr<MyObject> o; typedef boost::signals2::signal<void(void)> SigType; SigType s; // Error: can't convert std::tr1::shared_ptr<MyObject> to boost::weak_ptr... s.connect(SigType::slot_type(&MyObject::function, o.get()).track(o)); According to the docs you HAVE to use boost::shared_ptr. I'm just hoping there's some traits specialization or something I can provide so that I can get away with using the tr1 version instead (all our code is already written with tr1). Thanks! -Nathan

2 5

lexical problem
by pedro chaparro 14 Sep '09

14 Sep '09

hi, i'm working over a code to interchange messages using sockets, i have a server that when client connect to, server sends a char number(eg "100"), when client receives this string number, it has to addition +5 , to do that i need to change format from string to int and make sum operation, but when i do de change of format i get some error this message on the console window : bad lexical cast : source type value could not be interpreted as target Part of the code is : boost::array<char, 2> buf; boost::system::error_code error; size_t len = socket.read_some(boost::asio::buffer(buf), error); if (error == boost::asio::error::eof) break; // Connection closed cleanly by peer. std::string datos=buf.data(); int rxint; vector[2]=buf.data(); *rxint=boost::lexical_cast<int>(datos);* //(here is the problem) std::cout.write(buf.data(), len); do i making something wrong? -- Ing Pedro Alonso Chaparro Valero Ciudad Politecnica de la Innovación iTEAM - Mobile Communications Group Polytechnic University of Valencia C\ Camino de Vera S/N, Edificio 8G 46022 Valencia, Spain

2 1

[Filesystem] Problem with uncatchable exception when checking empty card reader
by Marco Wedekind 14 Sep '09

14 Sep '09

Hello, I am using the Filesystem library from boost 1.38.0 on Windows (Visual Studio 2005) like this: if (boost::filesystem::exists("W:") && boost::filesystem::is_empty("W:")) { ... do something useful ... } "W:" is assigned to an (usually) empty card reader slot. Unfortunately Filesystem's exists() function fails with an uncatchable exception. At least I cannot catch it... The exception is thrown by GetFileAttributesA() in operations.hpp: inline DWORD get_file_attributes( const char * ph ) { return ::GetFileAttributesA( ph ); } The exception pops up an error message that is titled "Windows - no disc" and it says: Exception Processing Message c0000013 Parameters 75b0bf9c 4 75b0bf9c 75b0bf9c Sadly, all I can do is to prefix a call to exists() with a call to GetVolumeInformationA() (from winbase.h) like this: if (GetVolumeInformationA("W:", NULL, NULL, NULL, NULL, NULL, NULL, NULL)) { if (boost::filesystem::exists("W:") && boost::filesystem::is_empty("W:")) { ... do something useful ... } } Is there any way to do this platform-independent? I have been searching the docs and the boost website, google and so on, to see if that can already be done with boost Filesystem. Since I did not find anything on this topic, I hope you can put me on the right track. Cheers, Marco Marco Wedekind | Software Developer | marco.wedekind(a)tomtom.com | +49(0)34124495-62 office | +49(0)34124495-25 fax TomTom Development Germany GmbH, Maximilianallee 4, D-04129 Leipzig, Germany | www.tomtomwork.com Amtsgericht Leipzig | HRB 22234 | Geschäftsführer: Thomas Schmidt, Marina Wyatt  Think before you print This e-mail message contains information which is confidential and may be privileged. It is intended for use by the addressee only. If you are not the intended addressee, we request that you notify the sender immediately and delete or destroy this e-mail message and any attachment(s), without copying, saving, forwarding, disclosing or using its contents in any other way. TomTom N.V., TomTom Software, Ltd or any other company belonging to the TomTom group of companies will not be liable for damage relating to the communication by e-mail of data, documents or any other information. This e-mail message contains information which is confidential and may be privileged. It is intended for use by the addressee only. If you are not the intended addressee, we request that you notify the sender immediately and delete or destroy this e-mail message and any attachment(s), without copying, saving, forwarding, disclosing or using its contents in any other way. TomTom N.V., TomTom Software, Ltd or any other company belonging to the TomTom group of companies will not be liable for damage relating to the communication by e-mail of data, documents or any other information.

2 1

[ptr_container] Dereferencing boost::signals2::signal from ptr_map
by Philipp Gildein 14 Sep '09

14 Sep '09

Hi, I got a huge problem with a boost::ptr_map. I am storing instances of boost::signals2::signal in it and try to dereference a iterator to one of those instances, to be able to call the operator () of the signal. This compiles correctly on Linux and gcc 4.4 but fails on Windows using Visual C++ 2008. The ptr_map is of type: typedef boost::ptr_map <std::string, boost::signals2::signal <void (Event)> > EventMap; And what i am trying to do is this: EventMap::iterator it = mEvents.find (event); if (it == mEvents.end ()) EXCEPTION ("Event doesn't exist"); (*it->second) (evt); The error message on Windows: C:\Program Files (x86)\Microsoft Visual Studio 9.0\VC\include \xutility(419) : error C2664: 'boost::signals2::detail::stack_allocator<T,n_stack_elements>::stack_allocator(boost::signals2::detail::stack_storage<T,10> *)': Konvertierung des Parameters 1 von 'boost::signals2::detail::stack_allocator<T,n_stack_elements>' in 'boost::signals2::detail::stack_storage<T,n_stack_elements> *' nicht möglich with [ T=std::_Aux_cont, n_stack_elements=10 ] and [ T=boost::shared_ptr<void>, n_stack_elements=10 ] and [ T=std::_Aux_cont, n_stack_elements=10 ] (First line translated is: Conversion of the first parameter from ... to .. not possible). For the complete code see http://github.com/rmbl/openspeak/raw/487dfcbea24df79216171f37d3102f8e76c8f7… and http://github.com/rmbl/openspeak/raw/487dfcbea24df79216171f37d3102f8e76c8f7… Thanks for any help. Regards Philipp Gildein

2 2

[program_options] simple test case fails
by Christian Henning 14 Sep '09

14 Sep '09

Hi there, I'm working against the trunk but the following program doesn't run properly. #include <iostream> #include <boost/program_options.hpp> using namespace std; namespace po = boost::program_options; int main(int argc, char* argv[]) { string input; po::options_description desc("Allowed options"); desc.add_options() ( "help,h" , "produce help message" ) ( "input,i" , po::value<string>( &input ), "Input File" ); po::variables_map vm; po::store( po::parse_command_line(argc, argv, desc), vm ); po::notify( vm ); if( vm.count( "help" )) { cout << desc << endl; return 1; } } When calling po::store() I get an assertion saying: "Expression: map/set iterators incompatible". My command line parameter is "--help". I'm using autolink and MSVC 2005. Regards, Christian

3 5

Building Boost 1.40
by Andrew Maclean 14 Sep '09

14 Sep '09

I built Boost 1.40 on Linux and installed it Ok. However are the libraries singlethreaded or multithreaded? eg. the library names are like this: libboost_python.so libboost_python.so.1.40.0 The older versions had -mt- in their name. eg. libboost_python-gcc43-mt.so etc. Thanks Andrew -- ___________________________________________ Andrew J. P. Maclean Centre for Autonomous Systems The Rose Street Building J04 The University of Sydney 2006 NSW AUSTRALIA Ph: +61 2 9351 3283 Fax: +61 2 9351 7474 URL: http://www.acfr.usyd.edu.au/ ___________________________________________

5 7

[interprocess] named_condition.timed_wait does not wait.
by Moritz 14 Sep '09

14 Sep '09

Hi all, I am fighting with the named_condition again. Currently I am using timed_wait but it does not behave like I expected. Sometimes it is okay (triggers on the given timeout) but sometimes it just returns immediately false (ignoring the timeout). Can someone give me a hint what I am doing wrong? Thanks in advance. Here is a simplified version of what I try to do: using namespace boost::interprocess; using namespace boost::posix_time; _process1_: (WRITER) scoped_lock<named_mutex> lock(mtx1); write_sth_to_shared_memory(); flag = true; named_condition1.notify_all(); named_condition2.wait(lock); _process2_: (READER) scoped_lock<named_mutex> lock(mtx2); while (true) { while (!flag) { flag = check_flag(); // set up timeout time_duration delay(milliseconds(200)); ptime timeout = ptime(second_clock::universal_time()); timeout += delay; // wait if (named_condition1.timed_wait(lock)) { check_for_interrupt(); break; } else { check_for_interrupt(); continue; } } do_some_reading_from_shared_mem(); named_condition2.notify(all); }

1 0

[units] meta_multiply units?
by Rupert Mazzucco 14 Sep '09

14 Sep '09

Hello, I cannot seem to figure out how to make a composite unit out of two existing units from the same system. For example, say I have a functor F which takes an argument of type F::arg_type = quantity<time> and returns a value of type F::ret_type = quantity<velocity> Now I want to write an integration function, which should return the correct type, something like template<class F> F::ret_type*F::arg_type // only conceptually integrate(F& f, typename F::arg_type a, typename F::arg_type b); so instantiating this with the above functor should produce a return type quantity<time*velocity==length>. How can I combine F::arg_type and F::ret_type to produce the correct return type for the function template? Thank you, Rupert -- Rupert Mazzucco <mazzucco(a)iiasa.ac.at> Research Scholar, Evolution and Ecology Program IIASA - Institute for Applied Systems Analysis Schlossplatz 1, 2361 Laxenburg, Austria Phone: +43 2236 807 522 Fax: +43 2236 713 13

2 3

Data type to handle C++ and Boost streams?
by Adam Nielsen 13 Sep '09

13 Sep '09

Hi all, Bit of a basic question - I'd like to have some functions that work with files (using std::fstream) but can also handle boost::iostreams. Is there a data type I can use that can handle both? For example: void writeSomeData(std::fstream out); I can't pass a boost::iostream::stream to this function. What type can I use to achieve this? Many thanks, Adam.

3 3

[boost.thread] boost thread on x64
by Pascal Kesseli 13 Sep '09

13 Sep '09

Hi friends Using the freshly created MinGW 64bit build, creating the boost 1.40 libraries with bjam worked flawlessly. However, when including boost/thread.hpp, I receive the following error: In file included from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/basic_timed_mutex.hpp:14, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/mutex.hpp:8, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/mutex.hpp:14, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/detail/thread.hpp:11, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/thread.hpp:22, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread.hpp:13, from ../src/main/com/emc/schedule/DailyRepetitiveTaskComposite.cpp:2: C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/interlocked_read.hpp: In function 'void boost::detail::interlocked_write_release(void* volatile*, void*)': C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/interlocked_read.hpp:71: error: cast from 'void*' to 'long int' loses precision In file included from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/mutex.hpp:8, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/mutex.hpp:14, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/detail/thread.hpp:11, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/thread.hpp:22, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread.hpp:13, from ../src/main/com/emc/schedule/DailyRepetitiveTaskComposite.cpp:2: C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/basic_timed_mutex.hpp: In member function 'void* boost::detail::basic_timed_mutex::get_event()': C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/basic_timed_mutex.hpp:152: error: cast from 'void*' to 'long int' loses precision make: *** [src/main/com/emc/schedule/DailyRepetitiveTaskComposite.o] Error 1 However, on the stated line, I can't even make out a cast. Is boost_thread win64 compatible? g++ version: g++.exe (GCC) 4.4.1 20090505 (prerelease) Copyright (C) 2009 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Thanks for any help and best regards Pascal

2 1

What is the way to access the data contained in a stream buffer?
by Ramon F Herrera 13 Sep '09

13 Sep '09

This is the relevant code: boost::asio::streambuf request; std::ostream request_stream(&request); request_stream << "GET " << argv[2] << " HTTP/1.0\r\n"; request_stream << "Host: " << argv[1] << "\r\n"; request_stream << "Accept: */*\r\n"; request_stream << "Connection: close\r\n\r\n"; // Send the request. boost::asio::write(socket, request); How can I convert the 'request.data' into a string or something? TIA, -Ramon

3 3

Re: [Boost-users] What is the way to access the data contained in a stream buffer?
by Anders Dalvander 13 Sep '09

13 Sep '09

Ramon F Herrera wrote: > I have a follow-up question of a more general nature. I think the Boost > libraries are the greatest thing since sliced bread, but there are times > when a simpler approach will suffice. We can see in these 2 lines of > code that we are mixing STL with Boost: > > boost::asio::streambuf request; > std::ostream request_stream(&request); > > Is there any STL class that can be used above, instead of > boost::asio::streambuf? > Something like std::ostringstream? std::ostringstream request_stream; request_stream << "GET " << argv[2] << " HTTP/1.0\r\n"; request_stream << "Host: " << argv[1] << "\r\n"; request_stream << "Accept: */*\r\n"; request_stream << "Connection: close\r\n\r\n"; std::string request = request_stream.str(); Regards, Anders Dalvander

1 0

Is there anything wrong with the Gmane newsgroup? + Interested in parsing tools and networking code
by Ramon F Herrera 13 Sep '09

13 Sep '09

Hello, I just joined the mailing list - Greetings to all. I have been trying for several day to post messages to the Boost Users newsgroup on Gmane. I didn't get any error message, but my postings never appeared. Boost is one of the best resources I have found in a very long time - Thanks for the effort! One of my main current interests is parsing. Trying to decide among the choices: - Regex - Spirit - Xpressive I could use some help with ASIO, too. -Ramon

4 10

PBGL / Dynamic Property Maps complexity
by Mathieu Malaterre 12 Sep '09

12 Sep '09

Hi there, I am slowly discovering (Parallel) BGL. Could someone confirm the following: All the BGL examples I found handle dynamic properties (data attached to a vertex) using 'Dynamic Property Maps'. If I understand correctly dynamic_properties are basically a std::map. The complexity to get a value from a std::map is O(log(n)). Thus a graph traversal of all values is O(n * log(n)). If this is correct, my question is: is there another approach where I could have a O(1) complexity to access data associated with an edge ? Thanks, -- Mathieu

2 2

[program_options]If a parameter in the command line contains white space, how to parse it ?
by yaoyansi 12 Sep '09

12 Sep '09

hi, all i use boost::program_options to parse cmd line parameters. Attachment has my code. And here is my test: tst.exe --wav c:/Program Files/Microsoft/a.wav --words "Hi, how are you?" --d "so,\ may\ be." the output is : wav:[c:/Program ] words:["Hi, ] d:["so,\ ] -------------------------------------------------- But, I want the result to be : wav:[c:/Program Files/Microsoft/a.wav ] words:[Hi, how are you?] d:[so, may be. ] What should I do now? Sorry for my poor English, And ,thanks in advance. ___________________________________________________________ 好玩贺卡等你发，邮箱贺卡全新上线！ http://card.mail.cn.yahoo.com/

3 3

[interprocess] 1.40 compile error
by Moritz 12 Sep '09

12 Sep '09

Hi, I just started to port my application from boost 1.37 to 1.40 in order to get the remove() methods work in an appropriate way. Problem is now that the compiler is complaining about my use of named_condition.wait(lock). Here is what I get: ../boost_1_40_0/boost/interprocess/sync/named_condition.hpp|156|error: invalid application of 'sizeof' to incomplete type 'boost::STATIC_ASSERTION_FAILURE<false>' ../boost_1_40_0/boost/interprocess/sync/named_condition.hpp|254|instantiated from 'void boost::interprocess::named_condition::wait(L&) [with L = boost::interprocess::scoped_lock<boost::interprocess::named_upgradable_mutex>]'| Thank you in advance for any hint.

2 3

[streams] surplus output generated
by Sven Heithecker 12 Sep '09

12 Sep '09

Hi all, the code below using boost::iostream produces unwanted surplus output: Write: this ist a test output split into two parts Print: this flushes previous output Write: another test output t split into two parts The last line is a fragment of the first line which should not be there. I am using boost 1_39, gcc 4.3.2 [gcc-4_3-branch revision 141291] What am I doing wrong here ? BTW: the code is a stripped demo code. Originally, "true" devices are used instead of the dummy "0", and I use some home-brewn classes (instead of just "string") which require specialized output handling depending on the used device, therefore the direct call into the stream object. However, this makes no difference. Regards, Sven --------------------------------------------------------------------- #include <iostream> #include <boost/iostreams/stream.hpp> #include <boost/iostreams/concepts.hpp> using namespace std; namespace io = boost::iostreams; // "demo" strem sink class CTestSink: public io::sink { public: CTestSink(int dummy) {} // iostreams requires constructor argument public: streamsize write(const char *s, streamsize n) { cout << "Write: " << s; return(n); } void Print(const string &str) const { cout << "Print: " << str << endl; } }; // the real stream typedef io::stream<CTestSink> CTestOStream; // specialized output for "string" objects CTestOStream &operator<<(CTestOStream &stream, string &str) { // make sure previous output is flushed // (not required in this example) stream.flush(); stream -> Print(str); // specialized output handling return(stream); } int main() { // dummy "0" required by boost:iostreams CTestOStream testostream(0); testostream << "this ist a test output "; testostream << "split into two parts" << endl; string str("this flushes previous output"); testostream << str; testostream << "another test output " << endl; } -- Sven Heithecker GPG Fingerprint: 52F7 06C2 BF51 96CE DFF7 CC89 1A6B DFD5 BEC2 02A6

2 2

[thread] multiple producers, single consumer - bosst-specific and generic questions
by Julien Claassen 11 Sep '09

11 Sep '09

Hello everyone! Thanks for all the help I already got. And excuse my poor understanding of of multithreading. I would like to implement a "multiple producer single consumer" pattern. My current solution is working with signals, which, I think is not very efficient. And also it doesn't work properly with the code I have, (see end of this mail). But besides that problem I have a generic question. If I worked with buffers and mutex, there are two choices, it seems: 1. Use one buffer, at the cost of deletion from the middle, when one producer terminates (so consumer won't communicate with a dead thread). 2. Have a buffer per producer, but also have a synchronisation per buffer and the consumer must look in several buffers, plus I don't know, how many producers there will be. This all should lead to a user interface, with different input-methods. So what would you suggest? It must be speedy and very CPU friendly. Thanks in advance for consideration. I'd also be happy for some suggested reading. Only one thing: printed books or documents in non-plain-text form besides .doc, .pdf and .ps aren't of any use to me, for I'm blind and using Linux text based environment. Kindest regards (For code, see below) Julien *** CODE SNIPPET *** boost::mutex my_mtx; // the Mutex for passing on events/chars // assumptions: // the following variables are passed to the Input object as a reference // int& its_q_size; // condition& its_in_condition; // condition& its_out_condition; // boost::signals2::signal<void (char)>& its_sig; void Input::run() { char input; boost::unique_lock<boost::mutex> lk(my_mtx); while (input != 'q') { cin >> input; while (its_q_size != 0) { its_in_condition.wait(lk); } its_sig(input); its_q_size = 0; its_out_condition.notify_all(); } } void Controller::run() { sig_t sig; // passed as its_sig condition in_condition, out_condition; // passed respectively as // its_incondition and its_out_condition int q_size = 0; // passed as char input; boost::unique_lock<boost::mutex> lk(my_mtx); Input *ip = new Input(in_condition,out_condition,sig,q_size); ip->connect(bind(&Controller::slot1, this, _1)); ip->connect(boost::bind(&Controller::slot2, this, _1)); thread runner(boost::bind(&Input::run, ip)); // why no third param _1 // here? With one it won't compiler! while (input != 'q') { while (q_size != 1) { out_condition.wait(lk); } // Do something with data received from the slots q_size = 0; in_condition.notify_all(); } runner.join(); } *** END OF CODE *** Effects: Read once, send signal, read again print info from first read and send signal again. Only really sync, when q is pressed. I expect due to runner-thread ending. -------- Music was my first love and it will be my last (John Miles) ======== FIND MY WEB-PROJECT AT: ======== http://ltsb.sourceforge.net the Linux TextBased Studio guide ======= AND MY PERSONAL PAGES AT: ======= http://www.juliencoder.de

4 8

boost::options, boost::shared_ptr with Intel C++ Compiler 11.x
by Marat Abrarov 11 Sep '09

11 Sep '09

Hi Boost C++ Libraries developers and users! I'm using boost 1.40. I have a project at http://sourceforge.net/projects/asio-samples/ (only SVN trunk is available now) It uses MS C++ Compiler (9.0 SP1 - MS Visual Studio 2008 SP1) and boost::program_options (+ boost::asio + boost::...). When I switched that project (I mean "echo_server") to Intel C++ Compiler 11.1.038 (I tried all 11.1.x) and built debug version (Debug Win32) (with addition of option /vmg to compiler command line - stupid Intel :) it works fine except shared_ptr-to-bool cast (for example: include/ma/echo/server/session_manager.hpp: 319). This issue I found only at "Debug Win32" build mode - at "Debug x64" all is fine and the built executable (echo_server.exe) works right. When I build "Release Win32" or "Release x64", the built executable don't work at all - it fails somewhere at the boost::program_options (I think at std::vector<std::string>::operator= or std::vector<std::string> copy-constructor). Does anybody: 1) tried to use boost::shared_ptr 2) tried to use boost::prorgam_options with Intel C++ Compiler 11.1.x? P.S. - If I change boost_1_40_0\boost\smart_ptr\detail\operator_bool.hpp: 9 - add "|| defined (BOOST_INTEL)" - then shared_ptr-to-bool cast works fine (Win32/x64 Debug/Release) Regards, Marat Abrarov.

1 0

Re: [Boost-users] [units,typeof] meta_multiply units?
by Rupert Mazzucco 11 Sep '09

11 Sep '09

> say I have a functor F which takes an argument of type > > F::arg_type = quantity<time> > > and returns a value of type > > F::ret_type = quantity<velocity> > > Now I want to write an integration function, which should > return the correct type, something like > > template<class F> > F::ret_type*F::arg_type // only conceptually > integrate(F& f, typename F::arg_type a, typename F::arg_type b); > > so instantiating this with the above functor should produce a > return type quantity<time*velocity==length>. How can I combine > F::arg_type and F::ret_type to produce the correct return type > for the function template? Attempted to solve this with the help of boost.typeof: template<class F> BOOST_TYPEOF_TPL(F::ret_type() * F::arg_type()) integrate(F& f, typename F::arg_type a, typename F::arg_type b); but MVC9 produces a error C2064: term does not evaluate to a function taking 0 arguments for the default constructor calls in the macro argument. Any ideas welcome. Thanks -- Rupert Mazzucco <mazzucco(a)iiasa.ac.at> Research Scholar, Evolution and Ecology Program IIASA - Institute for Applied Systems Analysis Schlossplatz 1, 2361 Laxenburg, Austria Phone: +43 2236 807 522 Fax: +43 2236 713 13

2 1

[bzip2 iostreams] [serialization] How to serialize an object into a bzip2 file and vice versa.
by Sebastian Korf 11 Sep '09

11 Sep '09

Hi. I right now managed to store objects via serialization onto harddisk. Because these files are still big and i used the textstream to serialize the object i decided to shrink the files...so far the plan :) I rebuild the iostreams with bzip support (that was also quite a pain ;) and now i can decompress a simple precompressed text file easily: int main() { using namespace std; using namespace boost::iostreams; ifstream file("E:\\test.txt.bz2", ios_base::in | ios_base::binary); filtering_streambuf<input> in; in.push(bzip2_decompressor()); in.push(file); ofstream fileOutput("E:\\test2.text"); copy(in,fileOutput); } But if i try to decompress a file which i serialized, bzip just runs forever doing nothing. SO my first question is, if someone knows why the serialized compressed files can not be decompressed. My second question is, if it is possible to serialize directly into a compressed bz2 file. I really looked around in the internet but still cannot get a clue so please respond. http://www.codeproject.com/KB/stl/zipstream.aspx?fid=16084&df=90&mpp=25&sor… http://lists.boost.org/Archives/boost/2003/10/53755.php Thanks, SK

2 1

[interprocess] named_condition wait question
by Moritz 11 Sep '09

11 Sep '09

Hi, I am using boost::interprocess::named_condition to synchronize 1-to-many communication. The reading processes are waiting on a named_condition that indicates the possibility to read. Problem is now that they wait until doomsday if no one triggers notify. So they can't quit the reading process themselves. Now I am thinking about using timed_wait instead of wait. That means checking some other exit-condition periodically. The question is now if the reader can miss the notify while he is checking that exit-condition? This is crucial to me because the readers have to notice new data in a shared memory segment. Thanks in advance. Problematic code: named_upgradable_mutex mtx; named_condition cond; { sharable_lock<named_upgradable_mutex> lock(mtx); while(true) { read(); cond.wait(lock); } } Possible solution?: named_upgradable_mutex mtx; named_condition cond; { sharable_lock<named_upgradable_mutex> lock(mtx); while(true) { read(); while (true) { if (cond.timed_wait(lock, 1 second)) break; else check_for_thread_interruption() } } }

2 2

iostreams or sockets?
by pedro chaparro 11 Sep '09

11 Sep '09

hi, in the asio examples there are two daytime examples , one use iostreams and the other one sockets, what criteria do i have to follows to choose one or the other? i've not really clear this concept? thanks -- Ing Pedro Alonso Chaparro Valero Ciudad Politecnica de la Innovación iTEAM - Mobile Communications Group Polytechnic University of Valencia C\ Camino de Vera S/N, Edificio 8G 46022 Valencia, Spain

2 1

help needed with bzip2/zlib with boost
by ChristinaDRS 11 Sep '09

11 Sep '09

Hello, I am trying to get the code below to compile in Visual Studios without luck. I downloaded and built the seperate zlib and bzip2 libraries and renamed them to: libboost_zlib-vc90-mt-gd-1_39.lib libboost_bzip2-vc90-mt-gd-1_39.lib because I was getting linking errors that I was missing thes elibs. but I get a bunch of unresolved linking errors now.. any idea what I might be doing wrong? I am guessing they must be needed to be built actually by boost? Is there any instructions on how to do this? Thanks!!! 1>------ Build started: Project: BoostCompression, Configuration: Debug Win32 ------ 1>Linking... 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::zlib::default_compression" (?default_compression@zlib@iostreams@boost@@3HB) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::zlib::deflated" (?deflated@zlib@iostreams@boost@@3HB) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::zlib::default_strategy" (?default_strategy@zlib@iostreams@boost@@3HB) 1>main.obj : error LNK2019: unresolved external symbol "int __cdecl test_main(int,char * * const)" (?test_main@@YAHHQAPAD@Z) referenced in function "public: int __thiscall boost::minimal_test::caller::operator()(void)" (??Rcaller@minimal_test@boost@@QAEHXZ) 1>main.obj : error LNK2019: unresolved external symbol "protected: __thiscall boost::iostreams::detail::bzip2_base::~bzip2_base(void)" (??1bzip2_base@detail@iostreams@boost@@IAE@XZ) referenced in function "public: __thiscall boost::iostreams::detail::bzip2_compressor_impl<class std::allocator<char> >::~bzip2_compressor_impl<class std::allocator<char> >(void)" (??1?$bzip2_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE@XZ) 1>main.obj : error LNK2019: unresolved external symbol "protected: __thiscall boost::iostreams::detail::zlib_base::~zlib_base(void)" (??1zlib_base@detail@iostreams@boost@@IAE@XZ) referenced in function __unwindfunclet$??0?$zlib_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE@ABUzlib_params@23@@Z$0 1>main.obj : error LNK2019: unresolved external symbol "protected: __thiscall boost::iostreams::detail::zlib_base::zlib_base(void)" (??0zlib_base@detail@iostreams@boost@@IAE@XZ) referenced in function "public: __thiscall boost::iostreams::detail::zlib_compressor_impl<class std::allocator<char> >::zlib_compressor_impl<class std::allocator<char> >(struct boost::iostreams::zlib_params const &)" (??0?$zlib_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE@ABUzlib_params@23@@Z) 1>main.obj : error LNK2019: unresolved external symbol "protected: void __thiscall boost::iostreams::detail::zlib_base::reset(bool,bool)" (?reset@zlib_base@detail@iostreams@boost@@IAEX_N0@Z) referenced in function "public: __thiscall boost::iostreams::detail::zlib_compressor_impl<class std::allocator<char> >::~zlib_compressor_impl<class std::allocator<char> >(void)" (??1?$zlib_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE@XZ) 1>main.obj : error LNK2019: unresolved external symbol "protected: __thiscall boost::iostreams::detail::bzip2_base::bzip2_base(struct boost::iostreams::bzip2_params const &)" (??0bzip2_base@detail@iostreams@boost@@IAE@ABUbzip2_params@23@@Z) referenced in function "public: __thiscall boost::iostreams::detail::bzip2_compressor_impl<class std::allocator<char> >::bzip2_compressor_impl<class std::allocator<char> >(struct boost::iostreams::bzip2_params const &)" (??0?$bzip2_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE@ABUbzip2_params@23@@Z) 1>main.obj : error LNK2019: unresolved external symbol "private: void __thiscall boost::iostreams::detail::zlib_base::do_init(struct boost::iostreams::zlib_params const &,bool,void * (__cdecl*)(void *,unsigned int,unsigned int),void (__cdecl*)(void *,void *),void *)" (?do_init@zlib_base@detail@iostreams@boost@@AAEXABUzlib_params@34@_NP6APAXPAXII@ZP6AX22@Z2@Z) referenced in function "protected: void __thiscall boost::iostreams::detail::zlib_base::init<class std::allocator<char> >(struct boost::iostreams::zlib_params const &,bool,struct boost::iostreams::detail::zlib_allocator<class std::allocator<char>,class std::allocator<char> > &)" (??$init@V?$allocator@D@std@@@zlib_base@detail@iostreams@boost@@IAEXABUzlib_params@23@_NAAU?$zlib_allocator@V?$allocator@D@std@@V12@@123@@Z) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::zlib::stream_end" (?stream_end@zlib@iostreams@boost@@3HB) 1>main.obj : error LNK2019: unresolved external symbol "public: static void __cdecl boost::iostreams::zlib_error::check(int)" (?check@zlib_error@iostreams@boost@@SAXH@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::zlib_compressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$zlib_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2019: unresolved external symbol "protected: void __thiscall boost::iostreams::detail::zlib_base::after(char const * &,char * &,bool)" (?after@zlib_base@detail@iostreams@boost@@IAEXAAPBDAAPAD_N@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::zlib_compressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$zlib_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2019: unresolved external symbol "protected: int __thiscall boost::iostreams::detail::zlib_base::deflate(int)" (?deflate@zlib_base@detail@iostreams@boost@@IAEHH@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::zlib_compressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$zlib_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::zlib::no_flush" (?no_flush@zlib@iostreams@boost@@3HB) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::zlib::finish" (?finish@zlib@iostreams@boost@@3HB) 1>main.obj : error LNK2019: unresolved external symbol "protected: void __thiscall boost::iostreams::detail::zlib_base::before(char const * &,char const *,char * &,char *)" (?before@zlib_base@detail@iostreams@boost@@IAEXAAPBDPBDAAPADPAD@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::zlib_compressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$zlib_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::bzip2::stream_end" (?stream_end@bzip2@iostreams@boost@@3HB) 1>main.obj : error LNK2019: unresolved external symbol "public: static void __cdecl boost::iostreams::bzip2_error::check(int)" (?check@bzip2_error@iostreams@boost@@SAXH@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::bzip2_compressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$bzip2_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2019: unresolved external symbol "protected: void __thiscall boost::iostreams::detail::bzip2_base::after(char const * &,char * &)" (?after@bzip2_base@detail@iostreams@boost@@IAEXAAPBDAAPAD@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::bzip2_compressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$bzip2_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2019: unresolved external symbol "protected: int __thiscall boost::iostreams::detail::bzip2_base::compress(int)" (?compress@bzip2_base@detail@iostreams@boost@@IAEHH@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::bzip2_compressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$bzip2_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::bzip2::run" (?run@bzip2@iostreams@boost@@3HB) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::bzip2::finish" (?finish@bzip2@iostreams@boost@@3HB) 1>main.obj : error LNK2019: unresolved external symbol "protected: void __thiscall boost::iostreams::detail::bzip2_base::before(char const * &,char const *,char * &,char *)" (?before@bzip2_base@detail@iostreams@boost@@IAEXAAPBDPBDAAPADPAD@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::bzip2_compressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$bzip2_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2019: unresolved external symbol "protected: int __thiscall boost::iostreams::detail::zlib_base::inflate(int)" (?inflate@zlib_base@detail@iostreams@boost@@IAEHH@Z) referenced in function "public: bool __thiscall boost::iostreams::detail::zlib_decompressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$zlib_decompressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2001: unresolved external symbol "int const boost::iostreams::zlib::sync_flush" (?sync_flush@zlib@iostreams@boost@@3HB) 1>main.obj : error LNK2019: unresolved external symbol "protected: int __thiscall boost::iostreams::detail::bzip2_base::decompress(void)" (?decompress@bzip2_base@detail@iostreams@boost@@IAEHXZ) referenced in function "public: bool __thiscall boost::iostreams::detail::bzip2_decompressor_impl<class std::allocator<char> >::filter(char const * &,char const *,char * &,char *,bool)" (?filter@?$bzip2_decompressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAE_NAAPBDPBDAAPADPAD_N@Z) 1>main.obj : error LNK2019: unresolved external symbol "protected: void __thiscall boost::iostreams::detail::bzip2_base::end(bool)" (?end@bzip2_base@detail@iostreams@boost@@IAEX_N@Z) referenced in function "public: void __thiscall boost::iostreams::detail::bzip2_compressor_impl<class std::allocator<char> >::close(void)" (?close@?$bzip2_compressor_impl@V?$allocator@D@std@@@detail@iostreams@boost@@QAEXXZ) 1>main.obj : error LNK2019: unresolved external symbol "private: void __thiscall boost::iostreams::detail::bzip2_base::do_init(bool,void * (__cdecl*)(void *,int,int),void (__cdecl*)(void *,void *),void *)" (?do_init@bzip2_base@detail@iostreams@boost@@AAEX_NP6APAXPAXHH@ZP6AX11@Z1@Z) referenced in function "protected: void __thiscall boost::iostreams::detail::bzip2_base::init<class std::allocator<char> >(bool,struct boost::iostreams::detail::bzip2_allocator<class std::allocator<char>,class std::allocator<char> > &)" (??$init@V?$allocator@D@std@@@bzip2_base@detail@iostreams@boost@@IAEX_NAAU?$bzip2_allocator@V?$allocator@D@std@@V12@@123@@Z) 1>D:\Debug\BoostCompression.exe : fatal error LNK1120: 29 unresolved externals [main.cpp] -------------------------------------------------------------------------------- #include <iostream> #include <sstream> #include <boost/assign/list_of.hpp> #include <boost/date_time/posix_time/posix_time.hpp> #include <boost/foreach.hpp> #include <boost/format.hpp> #include <boost/lexical_cast.hpp> #include <boost/numeric/conversion/cast.hpp> #include <boost/test/minimal.hpp> #include <boost/iostreams/copy.hpp> #include <boost/iostreams/device/back_inserter.hpp> #include <boost/iostreams/filter/bzip2.hpp> #include <boost/iostreams/filter/zlib.hpp> #include <boost/iostreams/filtering_stream.hpp> enum CompressionScheme { NO_COMPRESSION, ZLIB_COMPRESSION, BZIP2_COMPRESSION }; typedef boost::posix_time::ptime TimeType; //---------------------------------------------------------------------------- void add_compressor ( boost::iostreams::filtering_streambuf<boost::iostreams::output>& out, CompressionScheme scheme ) { switch (scheme) { case ZLIB_COMPRESSION: { out.push(boost::iostreams::zlib_compressor()); break; } case BZIP2_COMPRESSION: { out.push(boost::iostreams::bzip2_compressor()); break; } default: { break; } } } //---------------------------------------------------------------------------- void add_decompressor ( boost::iostreams::filtering_streambuf<boost::iostreams::input>& in, CompressionScheme scheme ) { switch (scheme) { case ZLIB_COMPRESSION: { in.push(boost::iostreams::zlib_decompressor()); break; } case BZIP2_COMPRESSION: { in.push(boost::iostreams::bzip2_decompressor()); break; } default: { break; } } } //---------------------------------------------------------------------------- std::string compress ( const std::string& data ) { std::stringstream compressed; std::stringstream decompressed; decompressed << data; boost::iostreams::filtering_streambuf<boost::iostreams::input> out; out.push(boost::iostreams::zlib_compressor()); out.push(decompressed); boost::iostreams::copy(out, compressed); return compressed.str(); } //---------------------------------------------------------------------------- std::string compress1 ( const std::string& data, CompressionScheme scheme ) { std::string compressed; boost::iostreams::filtering_streambuf<boost::iostreams::output> out; add_compressor(out, scheme); out.push(boost::iostreams::back_inserter(compressed)); boost::iostreams::copy(boost::make_iterator_range(data), out); return compressed; } //---------------------------------------------------------------------------- void compress2 ( const std::string& data, std::string& buffer, CompressionScheme scheme ) { buffer.clear(); boost::iostreams::filtering_streambuf<boost::iostreams::output> out; add_compressor(out, scheme); out.push(boost::iostreams::back_inserter(buffer)); boost::iostreams::copy(boost::make_iterator_range(data), out); } //---------------------------------------------------------------------------- std::string decompress ( const std::string& data ) { std::stringstream compressed; std::stringstream decompressed; compressed << data; boost::iostreams::filtering_streambuf<boost::iostreams::input> in; in.push(boost::iostreams::zlib_decompressor()); in.push(compressed); boost::iostreams::copy(in, decompressed); return decompressed.str(); } //---------------------------------------------------------------------------- std::string decompress1 ( const std::string& data, CompressionScheme scheme ) { boost::iostreams::filtering_streambuf<boost::iostreams::input> in; add_decompressor(in, scheme); in.push(boost::make_iterator_range(data)); std::string decompressed; boost::iostreams::copy(in, boost::iostreams::back_inserter(decompressed)); return decompressed; } //---------------------------------------------------------------------------- void decompress2 ( const std::string& buffer, std::string& data, CompressionScheme scheme ) { boost::iostreams::filtering_streambuf<boost::iostreams::input> in; add_decompressor(in, scheme); in.push(boost::make_iterator_range(buffer)); data.clear(); boost::iostreams::copy(in, boost::iostreams::back_inserter(data)); } //---------------------------------------------------------------------------- TimeType current_time ( ) { return boost::posix_time::microsec_clock::local_time(); } //---------------------------------------------------------------------------- double elapsed_seconds ( const TimeType& start_time ) { static const double MSEC_PER_SEC = 1000.0; TimeType end_time = current_time(); boost::posix_time::time_duration elapsed = end_time - start_time; return boost::numeric_cast<double>(elapsed.total_milliseconds()) / MSEC_PER_SEC; } //---------------------------------------------------------------------------- int test_main ( int /*argc*/, char* /*argv*/[] ) { const int NUM_ITERATIONS = 10000; const std::string send_data = "boo! how are you?"; const std::string base_statement = "ALGO %|1$-3s|: %2% cycles took %|3$0.3f| seconds"; double t0; // Try original algorithm { const std::string time_statement = base_statement + " (Original)\n"; TimeType start_time = current_time(); std::string received_data; for (int i = 0; i < NUM_ITERATIONS; ++i) { const std::string buffer = compress(send_data); received_data = decompress(buffer); } BOOST_CHECK(send_data == received_data); t0 = elapsed_seconds(start_time); std::cout << (boost::format(time_statement) % 0 % NUM_ITERATIONS % t0); } const std::string improvement_statement = base_statement + " (Improvement %|4$5.2f| %%)\n"; typedef std::vector<CompressionScheme> SchemeVectorType; const SchemeVectorType schemes = boost::assign::list_of(NO_COMPRESSION)(ZLIB_COMPRESSION)(BZIP2_COMPRESSION); // Try new algorithm 1 BOOST_FOREACH(CompressionScheme scheme, schemes) { TimeType start_time = current_time(); std::string received_data; for (int i = 0; i < NUM_ITERATIONS; ++i) { const std::string buffer = compress1(send_data, scheme); received_data = decompress1(buffer, scheme); } BOOST_CHECK(send_data == received_data); const std::string algo = std::string("1,") + boost::lexical_cast<std::string>(scheme); const double e = elapsed_seconds(start_time); const double improvement = ((t0 - e) / t0) * 100.0; std::cout << (boost::format(improvement_statement) % algo % NUM_ITERATIONS % e % improvement); } // Try new algorithm 2 BOOST_FOREACH(CompressionScheme scheme, schemes) { TimeType start_time = current_time(); std::string received_data; for (int i = 0; i < NUM_ITERATIONS; ++i) { std::string buffer; compress2(send_data, buffer, scheme); decompress2(buffer, received_data, scheme); } BOOST_CHECK(send_data == received_data); const std::string algo = std::string("2,") + boost::lexical_cast<std::string>(scheme); const double e = elapsed_seconds(start_time); const double improvement = ((t0 - e) / t0) * 100.0; std::cout << (boost::format(improvement_statement) % algo % NUM_ITERATIONS % e % improvement); } return 0; } -- View this message in context: http://www.nabble.com/help-needed-with-bzip2-zlib-with-boost-tp25401084p254… Sent from the Boost - Users mailing list archive at Nabble.com.

2 1

timeconv.inl
by Dan Smithers 11 Sep '09

11 Sep '09

I am porting some inherited code to MSVS 2008 This is also bringing along an upgrade from boost 1.32 to a newer version (probably 1.37). I have found a thread wrapper class in the code that uses time_to directly. This is defined in lib/thread/src/timeconv.inl and doesn't look like its meant to be used directly. The original code base has timeconv.inl in the boost include directory. Was timeconv.inl moved at some point in the past? Is this as bad as I think it is? thanks dan

3 3

Heterogeneous Bundled Properties (boost::detail::error_property_not_found)
by Mathieu Malaterre 11 Sep '09

11 Sep '09

Hi there, I am reading the following documentation: http://www.boost.org/doc/libs/1_40_0/libs/graph/doc/bundles.html I found the following test: libs/graph/test/bundled_properties.cpp, but I still do not understand how I can define a graph with heterogeneous vertex type. Could someone please let me know how to do that ? I tried the following two approaches: typedef adjacency_list < listS, vecS, directedS, boost::any >graph_type; and struct Fruit { virtual ~Fruit() {} }; typedef adjacency_list < listS, vecS, directedS, Fruit* >graph_type; But I when retrieving the vertex I always get a boost::detail::error_property_not_found Thanks -- Mathieu

1 0

Incorrect graph cut?
by David Doria 11 Sep '09

11 Sep '09

I made this simple graph: http://rpi.edu/~doriad/graph.png <http://rpi.edu/%7Edoriad/graph.png> The min cut between node 0 and node 3 should be 11, right? But it is returning 7. My code is below: #include <iostream> #include <boost/graph/adjacency_list.hpp> #include <boost/graph/kolmogorov_max_flow.hpp> using namespace boost; typedef adjacency_list_traits < vecS, vecS, directedS > Traits; typedef adjacency_list < vecS, vecS, directedS, property < vertex_name_t, std::string, property < vertex_index_t, long, property < vertex_color_t, boost::default_color_type, property < vertex_distance_t, long, property < vertex_predecessor_t, Traits::edge_descriptor > > > > >, property < edge_capacity_t, double, property < edge_residual_capacity_t, double, property < edge_reverse_t, Traits::edge_descriptor > > > > Graph; Traits::edge_descriptor AddEdge(Traits::vertex_descriptor &v1, Traits::vertex_descriptor &v2, property_map < Graph, edge_reverse_t >::type &rev, const double capacity, Graph &g); int main(int, char*[]) { Graph g; //a graph with 0 vertices property_map < Graph, edge_reverse_t >::type rev = get(edge_reverse, g); //add a source and sink node, and store them in s and t, respectively Traits::vertex_descriptor v0 = add_vertex(g); Traits::vertex_descriptor v1 = add_vertex(g); Traits::vertex_descriptor v2 = add_vertex(g); Traits::vertex_descriptor v3 = add_vertex(g); AddEdge(v0, v1, rev, 6.0, g); AddEdge(v0, v2, rev, 5.0, g); AddEdge(v1, v2, rev, 8.0, g); AddEdge(v2, v3, rev, 7.0, g); //find min cut double flow = kolmogorov_max_flow(g, v0, v3); // a list of sources will be returned in s, and a list of sinks will be returned in t std::cout << "Max flow is: " << flow << std::endl; property_map<Graph, edge_capacity_t>::type capacity = get(edge_capacity, g); property_map<Graph, edge_residual_capacity_t>::type residual_capacity = get(edge_residual_capacity, g); graph_traits<Graph>::vertex_iterator u_iter, u_end; graph_traits<Graph>::out_edge_iterator ei, e_end; for (tie(u_iter, u_end) = vertices(g); u_iter != u_end; ++u_iter) for (tie(ei, e_end) = out_edges(*u_iter, g); ei != e_end; ++ei) if (capacity[*ei] > 0) std::cout << "Source: " << *u_iter << " destination: " << target(*ei, g) << " capacity: " << capacity[*ei] << "residual cap: " << residual_capacity[*ei] << " diff: " << (capacity[*ei] - residual_capacity[*ei]) << std::endl; return 0; } Traits::edge_descriptor AddEdge(Traits::vertex_descriptor &v1, Traits::vertex_descriptor &v2, property_map < Graph, edge_reverse_t >::type &rev, const double capacity, Graph &g) { Traits::edge_descriptor e1 = add_edge(v1, v2, g).first; Traits::edge_descriptor e2 = add_edge(v2, v1, g).first; put(edge_capacity, g, e1, capacity); put(edge_capacity, g, e2, capacity); rev[e1] = e2; rev[e2] = e1; } The output is: Max flow is: 7 Source: 0 destination: 1 capacity: 6residual cap: 4 diff: 2 Source: 0 destination: 2 capacity: 5residual cap: 0 diff: 5 Source: 1 destination: 0 capacity: 6residual cap: 8 diff: -2 Source: 1 destination: 2 capacity: 8residual cap: 6 diff: 2 Source: 2 destination: 0 capacity: 5residual cap: 5 diff: 0 Source: 2 destination: 1 capacity: 8residual cap: 10 diff: -2 Source: 2 destination: 3 capacity: 7residual cap: 0 diff: 7 Source: 3 destination: 2 capacity: 7residual cap: 9 diff: -2 Here are my questions: 1) Why is the max flow wrong? 2) I'm confused what that output is showing - for example, there is a Source 1 Destination 2 edge that is not a real edge. It is also missing the edge from node 3 to node 1. 3) What is the best way to determine which nodes are on the source side of the cut, and which are on the sink side? The goal is to partition the graph into two sets. 4) Is it possible to pass a list of sources and a list of sinks to kolmogorov_max_flow instead of just a single source node and a single sink node? (Or can a different boost maxflow algorithm handle that?) These are just additional constraints on where the cut should be allowed to be placed. Maybe this is not the type of thing BGL is intended for? If it is, I really think the answers to these questions should be added to the documentation! Thanks, David

1 1

[boost.task] local_rr_ums.hpp missing
by Tan, Tom (Shanghai) 11 Sep '09

11 Sep '09

This header file is referenced while using static_pool. But it seems to be missing in either boost trunk or vault. Where can I get the latest version? Thanks.

1 0

boost thread on x64
by Pascal Kesseli 11 Sep '09

11 Sep '09

Hi friends Using the freshly created MinGW 64bit build, creating the boost 1.40 libraries with bjam worked flawlessly. However, when including boost/thread.hpp, I receive the following error: In file included from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/basic_timed_mutex.hpp:14, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/mutex.hpp:8, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/mutex.hpp:14, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/detail/thread.hpp:11, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/thread.hpp:22, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread.hpp:13, from ../src/main/com/emc/schedule/DailyRepetitiveTaskComposite.cpp:2: C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/interlocked_read.hpp: In function 'void boost::detail::interlocked_write_release(void* volatile*, void*)': C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/interlocked_read.hpp:71: error: cast from 'void*' to 'long int' loses precision In file included from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/mutex.hpp:8, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/mutex.hpp:14, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/detail/thread.hpp:11, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread/thread.hpp:22, from C:\Program Files\C++\boost\boost_1_40_0/boost/thread.hpp:13, from ../src/main/com/emc/schedule/DailyRepetitiveTaskComposite.cpp:2: C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/basic_timed_mutex.hpp: In member function 'void* boost::detail::basic_timed_mutex::get_event()': C:\Program Files\C++\boost\boost_1_40_0/boost/thread/win32/basic_timed_mutex.hpp:152: error: cast from 'void*' to 'long int' loses precision make: *** [src/main/com/emc/schedule/DailyRepetitiveTaskComposite.o] Error 1 However, on the stated line, I can't even make out a cast. Is boost_thread win64 compatible? g++ version: g++.exe (GCC) 4.4.1 20090505 (prerelease) Copyright (C) 2009 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Thanks for any help and best regards Pascal

2 1

Re: [Boost-users] RE : [lambda] for thread bind
by Boost lzw 10 Sep '09

10 Sep '09

Thanks. bind(&test_thread, s) works. How can I bind one boost::thread to another boost::thread? Here is what I want to do: void work_thread() { cout << "done" << endl; } void test_thread(boost::thread& t) { while (t.joinable()) { // do sth. this_thread::sleep(seconds(2)); } } int main() { boost::thread work_thread(work_thread); // this line does not compile boost::thread inquiry_thread(bind(&test_thread, work_thread ) ); work_thread.join(); inquiry_thread.join(); return 0; } Thanks in advance. Robert On Thu, Sep 10, 2009 at 4:24 PM, Eric MALENFANT < Eric.Malenfant(a)sagem-interstar.com> wrote: > Boost lzw wrote: > [snip] > > but the lambda version does not compile. Why? Thanks. > > ------------------------------------- > > > void test_thread(std::string s) > > { > > cout << "string is" << s << endl; > > } > > > > std::string s("I am a string"); > > boost::thread inquiry_thread(bind(test_thread, _1)(s) ); > > > > bind(test_thread, _1) creates a functor expecting one argument. Appending > "(s)" right after invokes that functor, passing it s as an argument. > > What you want is: bind(&test_thread, s) > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

2 1

[lambda] for thread bind
by Boost lzw 10 Sep '09

10 Sep '09

Hi there, I am playing with lambda. This following code works: ------------------------------------- void test_thread(std::string s) { cout << "string is" << s << endl; } boost::thread enquiry_thread(test_thread, s ); ------------------------------------- but the lambda version does not compile. Why? Thanks. ------------------------------------- #include"boost/lambda/lambda.hpp" #include"boost/lambda/bind.hpp" using namespace boost::lambda; void test_thread(std::string s) { cout << "string is" << s << endl; } std::string s("I am a string"); boost::thread inquiry_thread(bind(test_thread, _1)(s) );

2 1

Status of Boost.Extension from sandbox?
by Rex Kerr 10 Sep '09

10 Sep '09

I'm evaluating various plugin solutions for a project and am considering boost.extension as one of the alternatives. Looking at http://boost-extension.blogspot.com/ and the mailing list archives it appears that the project hasn't been active for a while. I have tried, unsuccessfully, to find a page detailing the current status of sandbox projects to determine whether or not it has been accepted for inclusion in future boost versions, has significant flaws preventing its inclusion, etc. I'm hesitant to choose a project that may be orphaned. Any guidance in finding such status updates, or outright answers to my questions, would be helpful. Thank you, -Rex

4 6

[thread]
by Alexander Heinrich 10 Sep '09

10 Sep '09

I want to determine if a given thread is still running or has already completed. I thought the joinable() method would provide this information, but unfortunately it seems that a thread does not automatically become Not-A-Thread after completion. I wrote a small app to verify this: <code> #include <iostream> using namespace std; #include <boost/thread.hpp> #include <boost/thread/mutex.hpp> #include <boost/date_time/posix_time/posix_time_types.hpp> using namespace boost; using namespace boost::posix_time; mutex ioMutex; void f() { mutex::scoped_lock lock(ioMutex); cout << "done" << endl; } int main(int argc, char** argv) { boost::thread t(f); while (t.joinable()) { { mutex::scoped_lock lock(ioMutex); cout << "not yet done" << endl; } this_thread::sleep(seconds(2)); } return 0; } </code> Output: not yet done done not yet done not yet done ... So what should I do instead if I want to know if a thread is still running? Best regards, Alexander Heinrich

2 1

transform_iterator requirement on the Iterator?
by Hicham Mouline 10 Sep '09

10 Sep '09

Hi, >From the docs, I don't see the Iterator argument is required to be default-constructible. I have a gcc4.3.3 error stack that looks like: /usr/include/boost-1_37/boost/iterator/iterator_adaptor.hpp: In constructor 'boost::iterator_adaptor<Derived, Base, Value, Traversal, Reference, Difference>::iterator_adaptor() [with Derived = boost::transform_iterator<Math::Curve1D<MathTest::Curve1D::CurveSVOTrait>::G etXIter, Math::CurveContainerIter<std::pair<double, double>, 4u, true>, boost::use_default, boost::use_default>, Base = Math::CurveContainerIter<std::pair<double, double>, 4u, true>, Value = const double, Traversal = boost::use_default, Reference = const double&, Difference = boost::use_default]': /usr/include/boost-1_37/boost/iterator/transform_iterator.hpp:100: instantiated from 'boost::transform_iterator<UnaryFunction, Iterator, Reference, Value>::transform_iterator() [with UnaryFunc = Math::Curve1D<MathTest::Curve1D::CurveSVOTrait>::GetXIter, Iterator = Math::CurveContainerIter<std::pair<double, double>, 4u, true>, Reference = boost::use_default, Value = boost::use_default]' /usr/lib/gcc/x86_64-redhat-linux/4.3.3/../../../../include/c++/4.3.3/bits/st l_algo.h:2086: instantiated from '_FIter std::lower_bound(_FIter, _FIter, const _Tp&) [with _FIter = boost::transform_iterator<Math::Curve1D<MathTest::Curve1D::CurveSVOTrait>::G etXIter, Math::CurveContainerIter<std::pair<double, double>, 4u, true>, boost::use_default, boost::use_default>, _Tp = double]' _____ math/interExtrapolators/interExtrapolate.hpp:75: instantiated from 'typename std::iterator_traits<fIterType>::value_type Math::InterExtrapolators::InterExtrapolate(xIterType, xIterType, fIterType, typename std::iterator_traits<_OI>::value_type, typename boost::call_traits<T>::param_type, typename boost::call_traits<Extrap>::param_type) [with Interp = Math::InterExtrapolators::StairCase1D, Extrap = Math::InterExtrapolators::StairCase1D, xIterType = boost::transform_iterator<Math::Curve1D<MathTest::Curve1D::CurveSVOTrait>::G etXIter, Math::CurveContainerIter<std::pair<double, double>, 4u, true>, boost::use_default, boost::use_default>, fIterType = boost::transform_iterator<Math::Curve1D<MathTest::Curve1D::CurveSVOTrait>::G etFIter, Math::CurveContainerIter<std::pair<double, double>, 4u, true>, boost::use_default, boost::use_default>]' ... mathTest/curve1D.cpp:72: instantiated from here /usr/include/boost-1_37/boost/iterator/iterator_adaptor.hpp:279: error: no matching function for call to 'Math::CurveContainerIter<std::pair<double, double>, 4u, true>::CurveContainerIter()' where it seems the compiler is looking for CurveContainerIter() with no arguments. but such constructor does not exist because the iterator has a member reference to the container. Or is this a requirement of std::lower_bound? Basically, the last line of the stack that is my code is xIterType xiter = std::lower_bound( xbegin, xend, x ); where xIterType is typedef boost::transform_iterator<GetXIter,ContainerConstIterType> xIterType; GetXIter is a unary function object, and ContainerConstIterType is CurveContainerIter<..., true> , true being for const'ness of the iterator. Xbegin, xend and x all of xIterType Regards,

2 3

[ptr_container] Transferring the Last Element from a ptr_vector
by Charles Brockman 10 Sep '09

10 Sep '09

I have two functions which swap elements between ptr_vectors. The first compiles and apparently works correctly. typedef boost::ptr_vector<Gene> GeneVectType; GeneVectType geneVect; void Gene::swapGene(Gene* other) { geneVect.transfer(geneVect.end(), other->geneVect.begin(), other->geneVect); other->geneVect.transfer(other->geneVect.end(), geneVect.begin(), geneVect); } Occasionally I must reverse the swap with this unswap function. void Gene::unswapGene(Gene* other) { // The line below is line 560 referred to in the error message. geneVect.transfer(geneVect.begin(), other->geneVect.rbegin(), other->geneVect); other->geneVect.transfer(other->geneVect.begin(), geneVect.rbegin(), geneVect); } This function should take the last element from each container and transfer it to the beginning of the other container. The unswapGene function will not compile. Here's the compiler message. C:\Boost SVN\trunk\boost/range/const_iterator.hpp(37) : error C2039: 'const_iterator' : is not a member of 'boost::reverse_iterator<Iterator>' with [Iterator=boost::void_ptr_iterator<std::_Vector_iterator<void *,std::allocator<void *>>,genprg::Gene>] C:\Boost SVN\trunk\boost/mpl/eval_if.hpp(63) : see reference to class template instantiation 'boost::range_const_iterator<C>' being compiled with [C=boost::reverse_iterator<boost::void_ptr_iterator<std::_Vector_iterator<void *,std::allocator<void *>>,genprg::Gene>>] C:\Boost SVN\trunk\boost/range/iterator.hpp(63) : see reference to class template instantiation 'boost::mpl::eval_if_c<C,F1,F2>' being compiled with [C=true, F1=boost::range_const_iterator<boost::reverse_iterator<boost::void_ptr_iterator<std::_Vector_iterator<void *,std::allocator<void *>>,genprg::Gene>>>, F2=boost::range_mutable_iterator<const boost::reverse_iterator<boost::void_ptr_iterator<std::_Vector_iterator<void *,std::allocator<void *>>,genprg::Gene>>>] C:\Boost SVN\trunk\boost/ptr_container/ptr_sequence_adapter.hpp(458) : see reference to class template instantiation 'boost::range_iterator<C>' being compiled with [C=const boost::reverse_iterator<boost::void_ptr_iterator<std::_Vector_iterator<void *,std::allocator<void *>>,genprg::Gene>>] ..\..\..\..\GSSTA\gene.cpp(560) : see reference to function template instantiation 'void boost::ptr_sequence_adapter<T,VoidPtrSeq,CloneAllocator>::transfer<genprg::Gene::GeneVectType,boost::reverse_iterator<Iterator>>(boost::void_ptr_iterator<VoidIter,T>,const Range &,PtrSeqAdapter &)' being compiled with [T=genprg::Gene, VoidPtrSeq=std::vector<void *,std::allocator<void *>>, CloneAllocator=boost::heap_clone_allocator, Iterator=boost::void_ptr_iterator<std::_Vector_iterator<void *,std::allocator<void *>>,genprg::Gene>, VoidIter=std::_Vector_iterator<void *,std::allocator<void *>>, Range=boost::reverse_iterator<boost::void_ptr_iterator<std::_Vector_iterator<void *,std::allocator<void *>>,genprg::Gene>>, PtrSeqAdapter=genprg::Gene::GeneVectType] Can anyone see what I'm doing wrong? -- Charles

6 11

[boost::multi_array] Is there simple method to delete certain row / column?
by Vladimir Petorov 10 Sep '09

10 Sep '09

Hello! I got two-dimensional array class based on boost::multi_array class. I need to delete some certain column or row of it. How to delete it with keeping the data? For example I have 2D array 6x6, and i need to delete 3th row and 4th column with keeping data from other rows and columns. Is it simple method (multi_array class function or some smart method) or should i create new array 5x5 and copy data in it except 3th row and 4th column? Thanks!

1 0

[BGL] DistanceMatrix type for johnson_all_pairs_shortest_paths
by Ralf Goertz 10 Sep '09

10 Sep '09

Hi, I spent a lot of time to figure out what the problem was. But the reason why there is a problem is still not clear. I modified the johnson_all_pairs_shortest_paths example program to allow for non-constant graphs. The example prog contained std::vector < int >d(V, (std::numeric_limits < int >::max)()); int D[V][V]; johnson_all_pairs_shortest_paths(g, D, distance_map(&d[0])); with V being const int whose value is known at compile time. In my program this is obviously not the case, therefore I defined const int V(num_vertices(g)); std::vector < int >d(V, (std::numeric_limits < int >::max)()); int D[V][V]; johnson_all_pairs_shortest_paths(g, D, distance_map(&d[0])); But this didn't compile, I got the error error: no matching function for call to ‘johnson_all_pairs_shortest_paths(Graph&, int [(long int)V][(long int)V], boost::bgl_named_params<int*, boost::vertex_distance_t, boost::no_property>)’ However, it is possible to access elements of D as D[i][j], even if V isn't known at compile time. This is (according to what I read at http://www.boost.org/doc/libs/1_39_0/libs/graph/doc/BasicMatrix.html ) the only constrained for D. Substituting int D[V][V] with vector<vector<int> > D(V,vector<int>(V)) solves the problem, but still why is there a problem in the first place? Ralf

3 3

Solaris Container
by Bernhard Duebi 10 Sep '09

10 Sep '09

Hello, I'm not a programmer, I'm only a system engineer, so please be gentle. One of our code producers compiled boost in a Solaris Zone/Container using SUN Studio. For testing he used a program called test. I guess it is part of the distribution. It tests if 2+2==4 with different calls to boost. The test program runs on real machines, but not in Containers. Looking at the output of truss I found a probable cause. The program climbs up the process tree using the proc filesystem until it reaches the root of the tree. In a real machine the init process has PID 1 and this seems the sign for the program to stop climbing. In a Container the zsched process has a random PID and its PPID is the same as the PID. This leads to an endless loop. In the test.cpp file there is not much code besides the add function and some calls to the boost library. So, I guess the process tree walk is done somewhere in the boost library. My fellow co-worker denies this strictly. As we both have no clue about boost, I want to ask you to sched some light on this incident. - Is it possible that boost does that process tree walk ? - Is this a known problem ? - Are there any hints how to solve this problem ? I talked to SUN and they say it's not their problem. There is no official whitepaper that requires that the init process always has PID 1. Any help is appreciated Sincerely Bernhard -- Minds are like parachutes They only function when open

6 8

how to suppress warning messages in boost file system
by Avi Bahra 10 Sep '09

10 Sep '09

Does anyone know how to suppress warning messages made by HP-UX aCC compiler. In particular: "/scratch/ma/ma0/hpia64/boost/boost_1_39_0/boost/filesystem/operations.hpp", line 579: warning #2236-D: controlling expression is constant && "boost::filesystem::complete() precondition not met" ); I get so many of these, its difficult to see the wood from the trees. Any help appreciated. Best regards, Ta, Avi

1 0

[asio] fails to compile on HP-UX aCC 11.23 due to ::pselect
by Avi Bahra 10 Sep '09

10 Sep '09

Boost 1.39/1.40 asio will not compile with acc A.06.20 on HPUX 11.23 : I have following error: "/scratch/ma/ma0/hpia64/boost/boost_1_39_0/boost/asio/detail/socket_ops.hpp", line 643: error #2282: the global scope has no "pselect" return error_wrapper(::pselect(nfds, readfds, The offending code in socket_ops.hpp is : inline int select(int nfds, fd_set* readfds, fd_set* writefds, fd_set* exceptfds, timeval* timeout, boost::system::error_code& ec) { ........... #if defined(__hpux) && defined(__HP_aCC) timespec ts; ts.tv_sec = timeout ? timeout->tv_sec : 0; ts.tv_nsec = timeout ? timeout->tv_usec * 1000 : 0; return error_wrapper(::pselect(nfds, readfds, writefds, exceptfds, timeout ? &ts : 0, 0), ec); #else int result = error_wrapper(::select(nfds, readfds, writefds, exceptfds, timeout), ec); if (result >= 0) clear_error(ec); return result; #endif } If I comment out the #ifdef with pselect in it, then everything appears to be ok. >From googling around it appears that pselect was only valid for certain OS versions, however #if can not detect this. Has anyone found a more reliable workaround ? Best regards, Ta, Avi

1 0

sending struct of int from Linux to Windows using boost::asio
by A.Agrawal＠patrick.com.au 10 Sep '09

10 Sep '09

Hello All, I am having trouble using boost:asio to send a simple struct message_header from server (linux) to the client (windows). typedef struct MessageHeader { uint32_t _data_length; //length of data attached uint8_t _message_type; //MESSAGE_TYPE uint8_t _segment_name; //SEGMENT_NAME uint16_t _request_id; //Request Id assigned by the client to the request to uniquely identify the request uint16_t _count_of_records; //Number of records affected by the operation, 0 means complete segment is affected. } MessageHeader; typedef struct Message { boost::array<char, header_length> _header_array; } Message Server side code (Linux): =============== MessageHeader request_header; request_header._data_length = 0; request_header._message_type = MSG_READ; request_header._segment_name = SEG_OOW; request_header._count_of_records = 0; request_header._request_id = 100; string _data_serialized = ""; uint8_t header[header_length]; //header_length is defined as 10 memcpy(header, (uint8_t*)(&(request_header)), header_length); std::vector<boost::asio::const_buffer> buffers; buffers.push_back(boost::asio::buffer(header, header_length)); buffers.push_back(boost::asio::buffer((_data_serialized).c_str(), _data_serialized.length())); boost::asio::async_write(_socket, buffers, boost::bind(&ClientSession::handle_write, shared_from_this(), boost::asio::placeholders::error)); Client Side code (Windows): ================ Message _read_message; MessageHeader _message_header; Handle_connect(....) { boost::asio::async_read(_socket, boost::asio::buffer(_read_msg._header_array, header_length), boost::bind(&DJClient::Handle_read_header, this, boost::asio::placeholders::error)); } Handle_read_header(...) { memcpy(&_message_header, read_msg._header_array.data(), header_length); } Surprisingly the same code works fine from "Windows to Windows" and "Windows to linux" but has problem when used on "Linux to Windows". When sent from Linux server, Windows server receives garbage data. Sending of normal ASCII characters from Linux to Windows work fine. Please help if anyone can. Thanks and Regards, Anil Agrawal

4 3

graph cut compilation error
by David Doria 10 Sep '09

10 Sep '09

I made a super simple example: A graph with 2 nodes and an edge between them. On trying to call kolmogorov_max_flow, I am getting: error: cannot convert 'boost::detail::error_property_not_found' to 'long int' in initialization Can anyone see what I am doing wrong? #include <iostream> // for std::cout #include <utility> // for std::pair #include <algorithm> // for std::for_each #include <boost/graph/graph_traits.hpp> #include <boost/graph/adjacency_list.hpp> #include <boost/graph/kolmogorov_max_flow.hpp> using namespace boost; // create a typedef for the Graph type typedef adjacency_list<vecS, vecS, bidirectionalS> Graph; int main(int,char*[]) { // declare a graph object Graph g(2); //a graph with 2 vertices // add the edges to the graph object for (int i = 0; i < 1; ++i) { add_edge(0, 1, g); //add an edge between node 0 and node 1 } //find min cut //typedef adjacency_list_traits<vecS, vecS, directedS> Traits; //if we want a directed graph typedef adjacency_list_traits<vecS, vecS, bidirectionalS> Traits; Traits::vertex_descriptor s, t; *//the error is on this line* long flow = kolmogorov_max_flow(g, s, t); // a list of sources will be returned in s, and a list of sinks will be returned in t std::cout << "Max flow is: " << flow << std::endl; return 0; } Also, I see that you can add edge weights like this: > const int num_nodes = 5; > E edges[] = { E(0,2), > E(1,1), E(1,3), E(1,4), > E(2,1), E(2,3), > E(3,4), > E(4,0), E(4,1) }; > int weights[] = { 1, 2, 1, 2, 7, 3, 1, 1, 1}; > > Graph G(edges + sizeof(edges) / sizeof(E), weights, num_nodes); > but if I want to add edges like this: for (int i = 0; i < 1; ++i) > { > add_edge(0, 1, g); //add an edge between node 0 and node 1 > } > How would I specify the edge weights? Thanks! David

2 10

[thread] Obtaining thread id on Windows
by Agustín K-ballo Bergé 09 Sep '09

09 Sep '09

I'm using Boost.Thread to create a thread that process the message queue on Windows. In order to send it a message via PostThreadMessage I need a thread id rather than a handle. Is there a way to obtain the native thread id from a boost::thread ? If not, any help on how to patch my local copy of the library? There is no documented way of getting a thread id from a thread handle in Windows XP. Thank you. Agustín K-ballo Bergé.-

6 8

[Spirit/Graph] New 1.40.0 compile errors in Spirit/Graph headers when using GCC with _GLIBCXX_DEBUG‏
by Tony Lewis 09 Sep '09

09 Sep '09

When I compile this script (saved as test.cpp) which includes a pair of Boost Graph headers : #include <boost/graph/adjacency_list.hpp> #include <boost/graph/depth_first_search.hpp> int main() { return 0; } ...using the compile command : g++ -I/usr/include/boost -D_GLIBCXX_DEBUG test.cpp -o test ...I get (this warning and) these errors from the Boost Spirit library: In file included from /usr/include/c++/4.3/backward/hash_set:64, from /usr/include/boost/graph/adjacency_list.hpp:25, from test.cpp:1: /usr/include/c++/4.3/backward/backward_warning.h:33:2: warning: #warning This file includes at least one deprecated or antiquated header which may be removed without further notice at a future date. Please use a non-deprecated interface with equivalent functionality instead. For a listing of replacement headers and interfaces, consult the file backward_warning.h. To disable this warning use -Wno-deprecated. In file included from /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/has_find.hpp:23, from /usr/include/boost/spirit/home/phoenix/stl/algorithm/querying.hpp:17, from /usr/include/boost/spirit/home/phoenix/algorithm.hpp:11, from /usr/include/boost/spirit/home/phoenix.hpp:10, from /usr/include/boost/graph/depth_first_search.hpp:24, from test.cpp:2: /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_map.hpp:38: error: wrong number of template arguments (4, should be 1) /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_map.hpp:28: error: provided for ‘template<class T> struct boost::is_std_map’ /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_map.hpp:38: error: expected unqualified-id before ‘>’ token /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_map.hpp:53: error: wrong number of template arguments (4, should be 1) /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_map.hpp:43: error: provided for ‘template<class T> struct boost::is_std_multimap’ /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_map.hpp:53: error: expected unqualified-id before ‘>’ token In file included from /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/has_find.hpp:24, from /usr/include/boost/spirit/home/phoenix/stl/algorithm/querying.hpp:17, from /usr/include/boost/spirit/home/phoenix/algorithm.hpp:11, from /usr/include/boost/spirit/home/phoenix.hpp:10, from /usr/include/boost/graph/depth_first_search.hpp:24, from test.cpp:2: /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_set.hpp:37: error: wrong number of template arguments (3, should be 1) /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_set.hpp:28: error: provided for ‘template<class T> struct boost::is_std_set’ /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_set.hpp:37: error: expected unqualified-id before ‘>’ token /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_set.hpp:51: error: wrong number of template arguments (3, should be 1) /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_set.hpp:42: error: provided for ‘template<class T> struct boost::is_std_multiset’ /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_set.hpp:51: error: expected unqualified-id before ‘>’ token In file included from /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/has_sort.hpp:22, from /usr/include/boost/spirit/home/phoenix/stl/algorithm/transformation.hpp:17, from /usr/include/boost/spirit/home/phoenix/algorithm.hpp:12, from /usr/include/boost/spirit/home/phoenix.hpp:10, from /usr/include/boost/graph/depth_first_search.hpp:24, from test.cpp:2: /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_list.hpp:36: error: wrong number of template arguments (2, should be 1) /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_list.hpp:28: error: provided for ‘template<class T> struct boost::is_std_list’ /usr/include/boost/spirit/home/phoenix/stl/algorithm/detail/./is_std_list.hpp:36: error: expected unqualified-id before ‘>’ token I don't get the errors if I use this compile command which doesn't define _GLIBCXX_DEBUG : g++ -I/usr/include/boost test.cpp -o test ...and I don't get the errors if I use this compile command which uses the previous 1.39 libraries : g++ -I/usr/include/boost-1_39 -D_GLIBCXX_DEBUG test.cpp -o test If I reverse the order of the headers when using the original compile command, I still get errors but different errors. My compiler is gcc 4.3.3 (Ubuntu 4.3.3-5ubuntu4), my OS is Ubuntu 9.04 and my kernel is 2.6.28-15-generic. Many thanks in advance for any help. _________________________________________________________________ View your other email accounts from your Hotmail inbox. Add them now. http://clk.atdmt.com/UKM/go/167688463/direct/01/

3 3

units use and weird cases....suggestions needed
by Noah Roberts 09 Sep '09

09 Sep '09

I'm using the units library to make sure values supplied to functions make sense, dimensionally, and are in the units expected. I've got a strange case I have to work with though. For the most part we've decided to standardize on the SI system. I write my functions to be system independent when possible, but most of what I'm working with is empirically based. For this I'll take the SI units expected and write the function only for that system (since other systems will use different equations entirely). The problem domain is fluid dynamics so enter the Kv and Cv values. Technically these are a measure of volumetric flow. For instance, Kv is defined as: the flow of water with temperature ranging 5 - 30 oC through a valve in cubic meters per hour (m3/h) with a pressure drop of 1 bar The problem is that engineers see this as a "unitless" value and treat it as having no units at all. They use Kv in SI based equations, not m3/s as we'd expect. Thus all equations being fed to us use Kv as if it were a natural part of the equation. Most of the time these dimensions do not compute dimensionally anyway but there's rare cases when they do. I have gotten the engineers (those giving me specs for code I write) to decide on Kv instead of doing both Kv and Cv (it's a basic conversion). The options I see are: 1. Convert both Kv and Cv into m3/s and require engineers to give equations with that in mind. This will be very unnatural for them though. 1a. Do the conversion but don't tell them I'm doing it. This one seems the least preferable as we've tried to make sure eng. documents and code match and further...it might be hard for maintenance developers later. 2. Pretend...just use m3ps and pretend I'm using Kv (m3/h). Don't convert or anything...just lie. I have a hard time with that one since it sort of goes against the purpose of the library and again would seem to introduce confusion for maintenance. 3. Use different types either in the form of a different unit "system" or using BOOST_STRONG_TYPEDEF...or something. What are some suggestions here?

2 4

Boost-Pro Windows Installer for Boost 1.40
by Klaim 09 Sep '09

09 Sep '09

Hi! I'm not sure how and when the windows installer for Boost 1.40 is planned. Where can I find the informations about that? Will it be available soon? I'm waiting for this installer before updating my Boost version. Thanks for you time. Joël Lamotte.

4 5

[iostreams] regex_filter how-to
by Michał Nowotka 09 Sep '09

09 Sep '09

Hello I have following problem: I need to filter some records from one file and save it to another in my c++ application. For example from this file: /////////////////// in.txt //////////////////////////////// http://google.com http://yahoo.com ... http://google.com/analytics //////////////////////////////////////////////////////////// I want to only extract lines that match regex: ^(?:http://google.com).* to get: //////////////// out.txt /////////////////////////////// http://google.com ... http://google.com/analytics ///////////////////////////////////////////////////////// So I wrote something like this: class Writer { public: Writer() :matchesCount_(0){} virtual std::string operator() (const boost::match_results<const char*>& result) { matchesCount_ = result.size(); return aux_; } int getMatchesCount() const { return matchesCount_; } virtual ~Writer(){} private: std::string aux_; //this i completely useless but i must return something in operator() int matchesCount_; }; /////////////////////////////////////////////////////////////////////////////// class FileWriter : public Writer { public: FileWriter(std::ostream* of) :of_(of) {} std::string operator() (const boost::match_results<const char*>& result) { *of_ << *result.begin() << endl; return Writer::operator()(result); } private: std::ostream* of_; }; /////////////////////////////////////////////////////////////////////////////// int main(int argc, char *argv[]) { boost::regex match_lower("^(?:http://google.com).*"); std::ofstream out("out.txt"); string str; filtering_istream first(boost::iostreams::regex_filter(match_lower, FileWriter(&out))); first.push(file_source("in.txt", ios_base::in)); first.ignore();// my output is a side effect of filtering so I don't have to process this stream return 0; } ///////////////////////////////////////////////////////////////////////////// It works fine for short files (IMO for files which size is smaller then size of stream buffer). But I work with very large files (~4,7 GB) and then this is not a good solution. Do you have any idea how to solve it? -- Regards Michał Nowotka

3 4

[BGL] Accessing graph_properties member
by Caligula 09 Sep '09

09 Sep '09

How can I access a member of graph_properties, such as a boolean or a vertex descriptor? A map might not be appropriate because there is only one graph. -Caligula

3 2

Re: [Boost-users] serialization::make_nvp parameters
by Hammond, John (UK New Malden) 09 Sep '09

09 Sep '09

> The space may be a problem. Boost.Serialization sticks the name directly into the XML, and <x:1 y:2></x:1 y:2> is bad. It appears that this was indeed the problem - a rookie mistake. By removing any spaces I am able to drop name.c_str() straight in to ::make_nvp() with no problems. To provide further context, the reason I want to assign the tags dynamically is because I am using the Serialization library in a simpler fashion than that for which it was designed. I only wish to provide a means of outputting the state of a window and I have no desire to export in a format that can be reliably read back in to the same system. Thanks for all your help, John ******************************************************************** This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. ********************************************************************

1 0

serialization::make_nvp parameters
by Hammond, John (UK New Malden) 09 Sep '09

09 Sep '09

Hello, I am hoping someone could answer a question I have regarding the make_nvp(..) function of the Serialization library. I am attempting to serialize a number of objects within a loop, and the name of the name-value-pair is to be assigned dynamically depending on some values taken from within the object that is to be serialized. I am currently performing the actions below: my_obj = GetMyObj(..); std::string temp = str( boost::format("x:%1% y:%2%") % _x % _y ); const char* const_temp = temp.c_str( ); ar & boost::serialization::make_nvp(const_temp, my_obj); This code compiles but will cause an exception on make_nvp. As far as I can tell, I am providing the function with the const char* that it requires, so am very confused as to why it is not performing as expected. Any help with this would be greatly appreciated. John Hammond ******************************************************************** This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. ********************************************************************

4 4

Re: [Boost-users] [shared_ptr] deleter that destroys shared_pt r -is it safe?
by Stefan Strasser 09 Sep '09

09 Sep '09

> This was fixed in 1.39, if I'm not mistaken (see revision 51643). Are you sure that it fails with the current implementation? no, "current" means 1.38 in my case.

1 0

[BGL] delete children subgraphs
by Marti Cuquet 09 Sep '09

09 Sep '09

Hello, I have a root subgraph from which I create a lot of children subgraphs, that use too much memory. How can I delete the children subgraphs after using them? Thanks, Marti

2 1

[shared_ptr] deleter that destroys shared_ptr - is it safe?
by Igor R 09 Sep '09

09 Sep '09

Hello, Is the following code legal and safe - a) according to the shared_ptr specs b) with the current boost::shared_ptr implementation Thanks! struct a { a() : p_(this, mem_fn(&a::delete_me)) {} void reset() { p_.reset(); } void delete_me() { delete this; } shared_ptr<a> p_; }; int main() { a* p = new a; p->reset(); }

3 5

[statechart] Broadcasting events to orthogonal states
by Vladimír Třebický 09 Sep '09

09 Sep '09

Hi all, first of all: thanks for the great library! I just dug into the boost::statechart tutorial trying to figure out how to deal with the following simple scenario: Let's say I have a complex application server represented by a single boost::state_chart with multiple modules (eg. network, database, etc.) represented by orthogonal spaces. I have a couple of system-wide events like "system shutdown". Handling these eventa is generally non-trivial and I'd like all the modules to process it independently. As I understand, statechart tries to deliver an event across al of the orthogonal spaces discarding it once it's processed by any of them (ie. by "return transit", "return discard_event", etc.). But I'd like these events to be delivered to _all_ orthogonal spaces no matter what they do with it. I could create a state for each of the orthogonal spaces. These wrappers would accept the system-wide events, translate them to local-events, post them locally and forward the system-wide event. But that's basically like having multiple statecharts for each of the modules and dispatching system-wide events manually. Thanks, Vladimir.

2 2

How to use boost 1.39 with eclipse
by manish4gupta 09 Sep '09

09 Sep '09

Hi , I am working on shared memory.I am using boost interprocess and regex module. I tried to install on ubuntu but it pop up errors for unrecognized function.So now i am planning to use boost interprocess and boost regex module in eclipse. How can i do that? Please help as i am in great need. Regards -- View this message in context: http://www.nabble.com/How-to-use-boost-1.39-with-eclipse-tp25356863p2535686… Sent from the Boost - Users mailing list archive at Nabble.com.

1 0

[asio] compile error on Solaris 10
by Wang, Paul 08 Sep '09

08 Sep '09

I'm including <boost/asio.hpp> and I'm getting the following compile error on Solaris 10 using gcc 3.4.3 with both Boost 1.39 and 1.40. In file included from /opt/boost_1_39_0/boost/asio/detail/socket_types.hpp:111, from /opt/boost_1_39_0/boost/asio/detail/win_iocp_io_service_fwd.hpp:24, from /opt/boost_1_39_0/boost/asio/io_service.hpp:37, from /opt/boost_1_39_0/boost/asio/basic_io_object.hpp:20, from /opt/boost_1_39_0/boost/asio/basic_socket.hpp:24, from /opt/boost_1_39_0/boost/asio/basic_datagram_socket.hpp:25, from /opt/boost_1_39_0/boost/asio.hpp:20, ... /usr/include/net/if.h:99: error: template argument required for `struct map' Does anyone know of a work around for this? Thanks, Paul

1 0

Can we pass variable argument list to boost format?
by ajil koshy 08 Sep '09

08 Sep '09

Hi, I'd like to know if there is a way by which we can pass the variable argument list to boost format. I have a function which creates formatted output strings for logging purpose. Currently, I'm using _vsnwprintf_s function internally to handle variable argument lists which the caller may be pass to this function. Can this be done using boost format? Thanks Ajil

2 1

Re: [Boost-users] shared_ptr and weak_ptr concurrency
by Jerry Jeremiah 08 Sep '09

08 Sep '09

Just to make sure I understand, am I right that this assumes x86/x64 CPUs and only those built in types up to register size (no 64 bit integers) and may not include single bytes in all circumstances? If you wrote code that depended on this assumption how could you be sure it wouldn't be ported to a box with a different CPU (I move stuff all the time between x86 and AIX, HPUX and sometimes a VAX). Can I make the same assumptions or not? And how can I be sure? Thanks, Jerry Message: 1 Date: Fri, 4 Sep 2009 11:58:46 -0400 From: John Dlugosz <JDlugosz(a)TradeStation.com> To: "boost-users(a)lists.boost.org" <boost-users(a)lists.boost.org> Subject: Re: [Boost-users] shared_ptr and weak_ptr concurrency Message-ID: <89030B4A18ECCD45978A3A6B639D1F240266A3F2C7(a)FL01EXMB01.trad.tradestation .com> Content-Type: text/plain; charset="utf-8" I know that on x86 and x64 architectures, assigning to or reading from any location up to the native general-purpose register size is atomic if the item in question is properly aligned for its size. That is, { a=b; in parallel with b=c; } will not read a partially-changed b, if b is declared in the normal manner. Reading oddly-aligned things out of a packed stream, or using pragmas to change the alignment options, may upset this. Furthermore, the cache is coherent among multiple CPUs or cores, even on a NUMA server. What you have to watch out for is when the compile actually issues the read or write, since it can us a register and save it back to memory much later, or re-arrange the requests. Furthermore, the chip queues requests to memory with reads having priority, so a write followed by a read needs special consideration. Assigning to a (non-volatile) char might do something ?interesting?. For example, if two separate char variables are declared, the compiler might keep them in registers and save them both out at the end with a single 16-bit write. The x86/x64 instruction set is conducive to that, but not to other cases. But in general an architecture might indeed merge separate variables to single larger register. The compiler might then re-save something that didn?t change, thus clobbering a change made on another thread. The current C++ standard does not address threads, so there is indeed no portable way to guarantee that. You have to encapsulate and implement for each architecture, and use compiler-specific extensions. It would be interesting to see a list of architectures noting whether or not primitive type reads and writes are atomic, at least verifying that they are even if there is nothing listed that doesn?t. I?m sure they would all have footnotes to that, as I described above for the one I?m familiar with. --John From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Kevin Kassil Sent: Friday, September 04, 2009 9:32 AM To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] shared_ptr and weak_ptr concurrency Stefan, On Thu, Sep 3, 2009 at 2:30 AM, Stefan Strasser <strasser(a)uni-bremen.de<mailto:strasser@uni-bremen.de>> wrote: ... why would you even need a lock here? the shared_ptr doc says that you can expect the same thread safety from shared_ptr as you can from built-in types. you can use multiple-readers-single-writer without any locks on built-in types. You can? Is assigning to a char or a double guaranteed to be atomic? How can the compiler guarantee that? -- What if there is some architecture for which it's not a single instruction assignment? Kevi

2 1

shared_ptr and weak_ptr concurrency
by Rajeev Rao 08 Sep '09

08 Sep '09

This is the first time I'm using boost in a multi-threaded env (linux x86_64,gcc 4). This question may have been asked in other forms. However, from what I've been able to search (google) up, I could not get a crystal clear answer. I'm essentially trying to use the solution provided in this page. http://onlamp.com/pub/a/onlamp/2006/05/04/smart-pointers.html?page=5. >From the boost documentation, it appears that this could be an undefined operation as the global shared pointer is being read and written to by multiple threads. Is that correct ? In case the link fails or someone wants more details, please read on. I've got a n reader threads and 1 writer thread. initializion Thread : shared_ptr< MyClass > global_ptr(createNewObject()) ; WriterThread :global_ptr.reset( createNewObject()) ReaderThreads:weak_ptr<MyClass> local_weak_ptr (globally_ptr) ;... if(shared_ptr< MyClass > local_shared_ptr = local_weak_ptr.lock() ) { // using local_shared_ptr.} else { // recreate weak ptr from global ?} thanks. Rajeev

7 16

[signals2] tracking intrusively ref-counted object
by Igor R 08 Sep '09

08 Sep '09

Hello, In my project I've got intrusively ref.counted objects (particularly, ATL COM-objects), which listen to signals of some asynchronous subsystem. Currently, when these objects connect to the signals, they bind their own intrusive smart-ptrs to the slot functor, like this: // pseudo code Object::init() { asyncSubsystem_.onSignal_.connect(bind(&Object::handleSignal, intrusive_from_this...)); // ensure the slot wouldn't bound to a dead object } Of course, this implies that the object cannot "die" until it's explicitly disconnected from the signal, so when the user of my library wants to get rid of such an object, he must call one more function (say, obj->close()) before resetting his smart-ptr to the object -- which is not just inconvenient, but also threatens the exception safety of user's code. Now I'd like to eliminate the need for this additional "finalization". For this purpose I have to: a) bind plain "this" to the slot functor -- so that the signal wouldn't be a "strong" client of Object b) eliminate race condition between slot invocation (coming from asyncSubsystem's thread) and the destruction of Object caused by resetting of user's intrusive ptr I tried to think of different ways to solve (b), but nothing seems to work so far... So my question is whether (b) is ever possible, and what would be the right solution for the whole issue. Thank you, Igor'.

3 7

[Thread] finding a good expression to wait...
by Julien Claassen 08 Sep '09

08 Sep '09

Hello everyone! I'm trying to build a simple user-interface. It reads events from the keyboard using cin in one thread and then yields to a controller, which does some work. I'm doing the waiting part in the threads using condition_variables. The input-threads "main-function" looks something like this: *** CODE SNIPPET *** condition input_cond, output_cond; // some other code void main_loop(condition& in, condition& out) { char input_key; boost::mutex::scoped_lock lk(my_global_mutex); while (input_key != 'q') { while (in.timed_wait(lk,system_time(second_clock::local() + seconds(1)) \ == false) // DEFINITELY NOT! good { } cin >> input_key; out.notify_one(); } } *** END OF CODE *** The controller/output main_loop looks similar only it uses out.timed_wait(...) and in.notify_one(), when the crucial task is done. Result is, both main_loops, when passed to a thread start and then it's deadlocked. I have seen examples of the producer/consumer pattern, which worked with buffers and they used conditions like: while (buffer_full == 0) or similar. I only have one key, no queueing, so what to do here? Please any good pointer/help/example is appreciated. Gratefully yours Julien -------- Music was my first love and it will be my last (John Miles) ======== FIND MY WEB-PROJECT AT: ======== http://ltsb.sourceforge.net the Linux TextBased Studio guide ======= AND MY PERSONAL PAGES AT: ======= http://www.juliencoder.de

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Exponential function
by amir ghanbari 08 Sep '09

08 Sep '09

Hi all, I'm new to boost and I wanted to know how can I compute exponential function in boost? thanx in advance!

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[bind] and [function] : question on binding member function
by Moritz 08 Sep '09

08 Sep '09

Hi, can someone explain to me why the following code crashes at the third call to "a.call_func" when "str" is dereferenced? Should'nt it crash when "this" is dereferenced? Thanks in advance. typedef boost::function<void (void)> Callback; class A { public: void set_cb_func( Callback cb ) { callback = cb; } void call_func() { callback(); } Callback callback; }; class B { public: B() : str(new std::string) {} ~B() { delete str; } void do_sth() { std::cerr << &(*this) << " " << *str << std::endl; *str += "string"; }; std::string * str; }; int main() { A a; { B b; a.set_cb_func(boost::bind(&B::do_sth, &b)); a.call_func(); a.call_func(); } a.call_func(); return 0; }

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[Accumulators] Matching via ADL.
by Robert Jones 08 Sep '09

08 Sep '09

In this code sequence: boost::accumulators::accumulator_set< long, boost::accumulators::features< boost::accumulators::tag::sum > > my_acc; long f( ) { using namespace boost::accumulators; return sum( my_acc ); } why do I need a using declaration? Shouldn't sum() be found via ADL? Using Boost 1.39 & MSVC 8. Thanks - Rob.

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[serialization] Workarounds for serialization of std::map / non-default constructors
by Chard 08 Sep '09

08 Sep '09

When serializing a std::map (specifically, the loading part) if either the key or value type of the map's pair is not default constructable then workarounds are required (note: this has only been confirmed with the std::map implementation provided with MSVC71). E.g.: {{{ #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/serialization/serialization.hpp> #include <boost/serialization/map.hpp> #include <sstream> #include <utility> //////// // Example, non-default constructable class class X { public: X(int i) : i_(i) {} private: int i_; friend class boost::serialization::access; template <typename A> void serialize(A &ar, const unsigned) {} }; template <typename A> inline void load_construct_data(A &ar, X * a, const unsigned) { ::new(a)X(1); // e.g. } ////////////////////////////////////////// void test_ser_pair() { std::map<double, X> theMap; theMap.insert(std::make_pair(0.5, X(1))); std::string text; { std::ostringstream ostr; boost::archive::text_oarchive arch(ostr); arch & theMap; text = ostr.str(); } { std::istringstream istr(text); boost::archive::text_iarchive arch(istr); // Next line doesn't compile under MSVC7.1 because the serialization // of map uses the default constructor of std::pair. arch & theMap; } } }}} My current workaround is to provide a specialization of just the std::pair constructor for my map's pair, but it would be nice if the library could provide a workaround.

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Re: [Boost-users] Trying to serialize observer pattern - both subject and observers with pionters
by Mikael Carlsson 08 Sep '09

08 Sep '09

Hi, > > I am using the observer pattern in a design and would like to make > > both subject and observers serializable. The subject hold a > base class > > pointer to the observes and the observers holds a base > class pointer > > to the subject. > > > > If I have understood the library correct I must register > the class for > > base class pointers in order to serialize the class pointer. > > Nope - you just have to indicate the base class for each class that > has one. I have included a small piece of code. It illustrates how I have interpreted the documentation. As you can see I use BOOST_CLASS_EXPORT (from what I read above, this is not needed). If I exclude the BOOST_CLASS_EXPORT I get "unregistered class" exception. If I include it, it appears to works but I get seg. fault during main exit (most likely a different problem related to my environment). I guess that I am using some parts of the library incorrect. > > This > > means that I must include the concrete subject in the concrete > > observers and vice versa. > > The means that I will run into circular dependencies. > > Nope C++ doesn't permit a circular derived/base class structure Understood, but I do not have a circular dependency between derived/base class, but with concrete observable(subject) and concrete observers. > > > > I guess that I am missing something here, the observer > pattern must be > > frequently used and be serialized. > > You're confusing the class structure which cannot be circular with a > seqence of pointers which can be circular. I guess you are right, I think I understand. > The library can handle circular pointer references with no problem. Understood (and agreed) / Mikael Carlsson

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Trying to serialize observer pattern - both subject and observers with pionters
by Mikael Carlsson 08 Sep '09

08 Sep '09

Dear list, I am using the observer pattern in a design and would like to make both subject and observers serializable. The subject hold a base class pointer to the observes and the observers holds a base class pointer to the subject. If I have understood the library correct I must register the class for base class pointers in order to serialize the class pointer. This means that I must include the concrete subject in the concrete observers and vice versa. The means that I will run into circular dependencies. I guess that I am missing something here, the observer pattern must be frequently used and be serialized. Have anyone used the observer pattern and managed to serialize both observers and subject with pointers included. / Mikael

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[variant] how to in-place construct a variant
by Stefan Strasser 07 Sep '09

07 Sep '09

I can't figure out how to in-place construct the contents of a boost::variant. the error message using GCC is merely 516 kb in size. from the boost.variant tutoral: > By default, a variant default-constructs its first bounded type, so v initially contains int(0). If this is not desired, or if the first bounded type is not default-constructible, a variant can be constructed directly from any value convertible to one of its bounded types. from the synopsis: > template<typename T> variant(const T &); > template<typename T> variant & operator=(const T &); so why does the following fail: struct A : noncopyable{ A(int); A &operator=(int); }; struct B{}; int main(){ A a(5); //ok a=5; //ok variant<A,B> var(5); //error var=5; //error } both error messages complain about noncopyable being - noncopyable. compiler is gcc 4.3.2 thank you

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[Signals2] connecting signals and pointers to objects
by Julien Claassen 07 Sep '09

07 Sep '09

Dear all! I'm trying to let several threads communicate using Boost.Signals2. Now I have encountered problems when working with pointers to my function-objects. could you please read this example code and give me pointers to solving these issues. *** CODE EXTRACT *** typedef boost::signals2::signal<void (char)> sig_t; class Base { public: boost::signals2::connection connect(const sig_t::slot_type&); protected: sig_t its_signal; }; boost::signals2::connection Base::connect(const sig_t::slot_type& subscriber) { return its_signal.connect(subscriber); } class Derived : public Base { public: void run(); }; void Derived::run() { // do something its_signal(); // something more to be done } class Function_object { public: void slot_func(char); void run(); }; void Function_object::slot_func(char c) { cout << "Hurrah, I received char c: " << c << endl; } void Function_object::run() { Base* my_base_pointer = new Derived(); my_base_pointer->connect(boost::bind(&Function_object::slot_func, \ this)); // Here I get errors from the Boost.Signals2 headers my_base_pointer->run(); } int main() { Function_object fo; thread taskrunner(boost::bind(&Function_object::run, &fo)); taskrunner.join(); return 0; } *** END OF CODE *** I compiled it with: gcc (Debian 4.3.2-1.1) 4.3.2 On Debian Lenny Linux. It seems I could have a reference to my Base or Derived object, when doing the connection, but no pointer. The goal is to have more than one derived class from Base and store them all in some kind of container or simple array. I tried making a vector of references to the Base cass, but as it should be an abstract data type, it didn't work. I would appreciate any help with this! Kindest regards Julien -------- Music was my first love and it will be my last (John Miles) ======== FIND MY WEB-PROJECT AT: ======== http://ltsb.sourceforge.net the Linux TextBased Studio guide ======= AND MY PERSONAL PAGES AT: ======= http://www.juliencoder.de

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[Interprocess] Problem reading or wrting to shared memory
by Thomas.Schulze＠camco.de 07 Sep '09

07 Sep '09

Hello, I created a simple class for storing information in shared memory (native Windows): template< class data> struct SharedData { SharedData<data>(): value(0), var(0.0), written(1), read(0){ std::cout<<" Objekt bei "<<this<<" erzeugt!"<<std::endl;} int value; // just temporary, will be replaced by a more generic data type double var; // just temporary, will be replaced by a more generic data type boost::interprocess::interprocess_semaphore written,read; }; I created and mapped that memory like: boost::interprocess::windows_shared_memory shm (create_only,name, read_write,sizeof(SharedData<data>)); boost::interprocess::mapped_region region(shm,read_write); and assigned a new data structure to it's address with: pShared = new(region.get_address()) SharedData<data>(); with pShared: SharedData<data>* pShared; But when I try to access the stored data with this pointer my program simply quits. Probably I am making a really silly mistake? Kind regards, Thomas Tel.: +49 2762 408-0 Fax.: +49 2762 408-10 Internet: http://www.camcoaudio.com CAMCO Produktions- und Vertriebs-GmbH f�r Beschallungs- und Beleuchtungsanlagen - Fischpicke 5 - 57482 Wenden - Amtsgericht Siegen HRB 7075 - Gesch�ftsf�hrer: Joachim St�cker, Reiner Sassmann, Carsten Wegner

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[asio] SSL enabled http server3 example is blocking
by Mariusz Wojtysiak 07 Sep '09

07 Sep '09

Hello, I noticed, that my ssl server implemented with boost::asio, which use pool of 10 threads, use only first working thread. Even if I put long running operation (like: std::cin > c; ) in handler of ssl request, request from second client is hung until running operation finish in first thread. Similar problem was described in archived post: "[asio] SSL enabled http server3 example is blocking" http://groups.google.pl/group/boost-list/browse_frm/thread/c26432c90020e6d9… After a few hours of debugging asio, I found a reason: Class openssl_stream_service implement ssl operations (like async_handshake, async_write_some...) using strand_ member, which is type of io_service::strand. This causes that two ssl operations using the same ssl stream cannot be running in the same time. Here is piece of code, which I had on my server to handle client request: void Request::handleClientRequest() { boost::asio::async_read_until( m_sessionPtr->getSocket(), m_headerBuffer, '\n', boost::bind( &Request::readHeaderHandler, shared_from_this(), boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred ) ); } void Request::readHeaderHandler( const boost::system::error_code &error, std::size_t bytesTransferred ) { // long running operation char c; } Method readHeaderHandler() is called from io_service::strand, so during this long running operation any other requests from clients have to wait! Solution it simple and works fine for me: Instead of calling long operations directly in handler, post operation to io_service, like here: void Request::readHeaderHandler( const boost::system::error_code &error, std::size_t bytesTransferred ) { m_ioService.post( boost::bind ( &Request::executeCommandHandler::executeCommandHandler, shared_from_this() ) ); } void Request::executeCommandHandler() { // long running operation char c; } This way, readHeaderHandler() return immediately from current srand operation (so other client's request may be handled) and executeCommandHandler() is called a bit later.

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Looking for bgl-book.pdf
by Mathieu Malaterre 07 Sep '09

07 Sep '09

Hi there, Does anyone has a copy of bgl-book.pdf ? I am running a debian/linux system and there are no tool to decompress 'sit' file. Ref: http://www.informit.com/store/product.aspx?isbn=0201729148 or directl link: http://www.informit.com/content/images/0201729148/CDContents/0201729148_CD.… Thank you -- Mathieu

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[math] gamma distribution's quantile performance
by Christian Henning 06 Sep '09

06 Sep '09

Hi there, I have created a test which times the performance of boost::math::quantile( ... ) when using a gamma distribution. I ran it against source code we use here at work, for ages. It can be found here: http://people.sc.fsu.edu/~burkardt/cpp_src/dcdflib/dcdflib.html The old source code is about 2x times faster than the boost version. MS Visual Studio 2005: boost: 35.4sec att_bell:19sec Intel 11.1: boost: 21.4sec att_bell: 11.2sec Question is if there is a way to incorporate such a function into boost::math? As far, as I can tell the results are almost identical. Regards, Christian Here the code: #include <dcdflib.h> #include <boost/math/distributions/gamma.hpp> #include <boost/timer.hpp> double min_mean = 2000; // 2,000 double max_mean = 500000000; //500,000,000 double min_std = 10000; // 10,000 double max_std = 100000000; // 100,000,000 double min_max = 600000000; // 600,000,000 double max_max = 1000000000; // 1,000,000,000 const std::size_t max_year = 5000000; // 5,000,000 const double right = 0.999; const double left = 0.001; inline double get_rand() { return static_cast< double >( std::rand() ) / static_cast< double >( RAND_MAX ); } inline void boost_( boost::math::gamma_distribution<>& d, double q ) { double value = boost::math::quantile( d, q ); } inline void att_bell( double alpha, double beta, double q ) { double q_Minus1 = 1 - q; double value = 0.0; double bound = 0.0; int which = 2; int status = 0; cdfgam( &which , &q , &q_Minus1 , &value , &alpha , &beta , &status , &bound ); } int main() { // boost { std::srand( 0 ); boost::timer timer; for( std::size_t y = 0; y < max_year; ++y ) { if(( y % 100000 ) == 0 ) std::cout << y << std::endl; double mean = get_rand() * ( max_mean - min_mean ) + min_mean; double std = get_rand() * ( max_std - min_std ) + min_std; double alpha = mean * mean / std / std; // shape parameter double beta = mean / alpha; // scale parameter boost::math::gamma_distribution<> d( alpha, beta ); boost_( d, right ); boost_( d, left ); } std::cout << "Boost - Time elapsed: " << timer.elapsed() << " sec" << std::endl; } // att bell { std::srand( 0 ); boost::timer timer; for( std::size_t y = 0; y < max_year; ++y ) { if(( y % 100000 ) == 0 ) std::cout << y << std::endl; double mean = get_rand() * ( max_mean - min_mean ) + min_mean; double std = get_rand() * ( max_std - min_std ) + min_std; double alpha = mean * mean / std / std; // shape parameter double beta = mean / alpha; // scale parameter att_bell( alpha, beta, right ); att_bell( alpha, beta, left ); } std::cout << "ATT Bell - Time elapsed: " << timer.elapsed() << " sec" << std::endl; } return 0; }

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