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[ptr_container] ptr_map and cloning issues
by Robert Dailey 06 Feb '09

06 Feb '09

I have a ptr_map as follows: typedef boost::ptr_map<std::string, Texture> TextureContainer; I only use forward declarations of Texture where needed. When I'm iterating over an instance of TextureContainer, I expect to not have to do more than use the forward declaration since technically we're only iterating pointer values and the definition of Texture is not needed for this. So when I do this: TextureContainer myTextures; TextureContainer::const_iterator it = myTextures.find( "some key" ); The above (second line) results in an extremely complex and long compiler error, but the important part of the error says what I have pasted below. Why is this error happening? Is it trying to clone Texture objects? This shouldn't be happening. *boost/ptr_container/clone_allocator.hpp(34) : error C2514: 'rs::Texture' : class has no constructors C:\IT\work\planb\components\rs/renderer/TextureFwd.hpp(6) : see declaration of 'rs::Texture' C:\IT\work\planb\third_party\boost\1_37_0\boost/ptr_container/clone_allocator.hpp(55) : see reference to function template instantiation 'T *boost::new_clone<U>(const T &)' being compiled*

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boost and std collisons in c++0x
by Ein Held 06 Feb '09

06 Feb '09

Hello I would like to know more about boost's general attitude towards c++0x and the collisions of boost with std. As of now, we move both, ::boost- and ::std-namesspace in the global namespace via using xxx. This is exactly what we want - boost and the stl are both such fundamental libraries that using an explicit namespace specifier everytime we want to use content of these namespaces is not accaptable. This would just blow the code and make it unreadable. Once we move up to c++0x, we will not be able to keep this way of coding up. ::std::tr1 is merged into ::std and so the former tr1 classes will collide with the boost ones if explicit namespace identifiers are missing. I would like to stress the fact that code, perfectly fine to the boost documentation, will fail to compiler most likely. #include <iostream> //This one might include <array> using namespace std; #include <boost/array.hpp> using namespace boost; array<int,1> blub; //fail Is there anything planned to prevent this happen? Thank you

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[iterator] - does there exist an opposite of Function Output Iterator?
by Michael Fawcett 06 Feb '09

06 Feb '09

http://www.boost.org/doc/libs/1_37_0/libs/iterator/doc/function_output_iter… Shows a unary function being adapted as an OutputIterator. Does Boost have something that does the opposite, i.e. takes an OutputIterator and adapts it as a unary function object? In my own code I currently have: template <typename OutputIterator> struct output_iterator_function { explicit output_iterator_function(OutputIterator i) : iter(i) { } template <typename T> void operator()(const T &v) { *iter++ = v; } OutputIterator iter; }; template <typename OutputIterator> output_iterator_function<OutputIterator> make_output_iterator_function(OutputIterator i) { return output_iterator_function<OutputIterator>(i); } If this doesn't already exist in Boost.Iterator, it seems like it would nicely complement the already existing function_output_iterator. --Michael Fawcett

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glibc detected corrupted doubly-linked list (unit test)
by Ross Boylan 05 Feb '09

05 Feb '09

I get error shown below when I try to test my program. It appears to be coming directly out of the unit test framework, though this is after a test, and so my code could have done something. Can anyone help me determine what is going on or how to fix it? Valgrind shows the error, but it's source is mysterious. This was generated on Debian GNU/Linux etch with 64 bit Xeon and gcc. The same tests run fine on Debian testing with 32 bit AMD and OS-X on 64 bit powerpc (although I think the older version of the OS on the machine is mostly 32 bit). *** glibc detected *** corrupted double-linked list: 0x00000000005fd2a0 *** Program received signal SIGABRT, Aborted. 0x00002affd559207b in *__GI_raise () from /usr/lib/debug/libc.so.6 Current language: auto; currently c (gdb) where #0 0x00002affd559207b in *__GI_raise () from /usr/lib/debug/libc.so.6 #1 0x00002affd559384e in *__GI_abort () from /usr/lib/debug/libc.so.6 #2 0x00002affd55c85f9 in __libc_message () from /usr/lib/debug/libc.so.6 #3 0x00002affd55cd9cc in malloc_consolidate () from /usr/lib/debug/libc.so.6 #4 0x00002affd55cf789 in _int_malloc () from /usr/lib/debug/libc.so.6 #5 0x00002affd55d116d in *__GI___libc_malloc () from /usr/lib/debug/libc.so.6 #6 0x00002affd518f93d in operator new () from /usr/lib/libstdc++.so.6 #7 0x00002affd516e5d1 in std::string::_Rep::_S_create () from /usr/lib/libstdc++.so.6 #8 0x00002affd516ef8b in std::string::_Rep::_M_clone () from /usr/lib/libstdc++.so.6 #9 0x00002affd516f895 in std::string::reserve () from /usr/lib/libstdc ++.so.6 #10 0x00002affd51690a5 in std::basic_stringbuf<char, std::char_traits<char>, std::allocator<char> >::overflow () from /usr/lib/libstdc++.so.6 #11 0x00002affd516da8d in std::basic_streambuf<char, std::char_traits<char> >::xsputn () from /usr/lib/libstdc++.so.6 #12 0x00002affd5163512 in std::operator<< <std::char_traits<char> > () from /usr/lib/libstdc++.so.6 #13 0x00002affd4fbb175 in boost::unit_test::results_collector_t::test_unit_finish () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #14 0x00002affd4fb8180 in boost::unit_test::framework_impl::visit () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #15 0x00002affd4fc9f1b in boost::unit_test::traverse_test_tree () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #16 0x00002affd4fb72d8 in boost::unit_test::framework::run () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #17 0x00002affd4fc2b35 in main () from /usr/lib/libboost_unit_test_framework-gcc-mt-1_33_1.so.1.33.1 #18 0x00002affd557f4ca in __libc_start_main () from /usr/lib/debug/libc.so.6 #19 0x000000000040420a in _start () at ../sysdeps/x86_64/elf/start.S:113 -- Ross Boylan wk: (415) 514-8146 185 Berry St #5700 ross(a)biostat.ucsf.edu Dept of Epidemiology and Biostatistics fax: (415) 514-8150 University of California, San Francisco San Francisco, CA 94107-1739 hm: (415) 550-1062

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Citing Boost libraries
by Niko Vuokko 05 Feb '09

05 Feb '09

Hi, I remembered once seeing an entry on the website saying how one should cite the Boost project. Now however I can't find it when I'd need it. Thus, is 'Boost Project, http://www.boost.org' enough or is there some policy on citing? Niko Vuokko

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Any restriction on adding a boost/sandbox library to dmoz (open directory)?
by er 05 Feb '09

05 Feb '09

Hello, Are there any restrictions on adding a boost/sandbox library that I wrote under the boost license to dmoz (open directory project) to facilitate online searches?

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Re: [Boost-users] proto: analytical-only math functions
by Hicham Mouline 05 Feb '09

05 Feb '09

> ----- Original Message ----- > From: "Eric Niebler" <eric(a)boost-consulting.com> > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] proto: analytical-only math functions > Date: Thu, 05 Feb 2009 08:40:05 -0800 > > > Hicham Mouline wrote: > > Hi Eric, > > > > Thank you for the LHS grammar. I have made the changes you suggested in the > > attached files. > > > > The main header <math.h> (I'll change this name later) includes constants > > (c0 ... c100), variables(x0... x100 and x y z S r q v t), basic functions > > from <cmath> and general functions defined by the user, with dimensions 0 to > > 100. > > > > Question1: With PP, I define constants c0 to c100, as non-const because I > > let the user initialize them to a integer variables or literals or floating > > point variables or literals. > > I don't understand, but it probably doesn't matter. PP is boost.preprocessor. I forgot attached files don't appear in the mailing list. template <unsigned int subscript> struct constant_tag {}; proto::terminal< constant_tag<0> >::type c0 = {{}}; // with preprocessor, i define c0 ... c100 I don't want lib users, in a first use, to have to define constant names nor variable names themselves. > > Does the non-constness matter? They are defined in a header file included by > > users of the library. > > You'll have linker trouble if two translation units include that header. You > should define them in a .cpp file and mark them as extern in the header. Right. Could i define them const and still assign values (like arithmetic literals) to them later on? > > > Queestion3: I made dimension_of a numerical metafunction with an embedded > > value member. > > OK, that's reasonable. > > > What is the convenience > > of making metafunctions numerical? > > I don't know what you're asking. I'm just asking about a general advice re whether to make metafunctions numerical whenever possible. > > Question4: What is a quick way to test fundef_lhs_grammar does what I > > intend? > > When I want to test a grammar, I define two functions like this: > > template<typename E> > void assert_matches( E const & ) > { > BOOST_MPL_ASSERT((proto::matches<E, fundef_lhs_grammar>)); > } > > template<typename E> > void assert_not_matches( E const & ) > { > BOOST_MPL_ASSERT_NOT((proto::matches<E, fundef_lhs_grammar>)); > } > > Then in main(), I can create expressions and pass them to one of these > functions. Either it matches or it doesn't, and I can find out at compile time. > Great, will do. I'll leave the grammar of the RHS of = operator till later. My next question is about my constants. I want to allow this example of syntax: c35 = any expression of integral or floating point literals, of c++ runtime variables of integral or fp type (no bool no enums) of _other_ constants Later, a constant will be either undefined, or defined. if undefined, evaluations of expressions with that constant will keep that constant in, otherwise, the constant will be replaced by its value How do I write the grammar that allows any expression, but just with those 4 possibilies (c35)? regards,

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boost::lambda: how to create indirect functor
by ＠ 05 Feb '09

05 Feb '09

prerequisites: struct C { void func(int i) {} }; void indirect(boost::function<void(C*)> f) { static C c; f(&c); } I need a functor that takes int and calls "indirect" passing there &C::func bound with that int. I imagine a solution like: boost::function<void(int)> result_functor = bind(indirect, bind(&C::func, protect(_1), _1)); receiving compilation error: "could not deduce argument" deep inside lambda library thanks -- View this message in context: http://www.nabble.com/boost%3A%3Alambda%3A-how-to-create-indirect-functor-t… Sent from the Boost - Users mailing list archive at Nabble.com.

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Re: [Boost-users] [boost] [SVG Plot] What happened to this library?
by Marc Viala 05 Feb '09

05 Feb '09

Hello, I have just checked out the latest release of SVG Plot library from https://svn.boost.org/svn/boost/sandbox/SOC/2007/visualization/ and tried to compile one source example w/ VC++ 7.1 against Boost 1.37.0 but the compilation failed. The file source is "1d_simple.cpp" from the of SVG Plot example directory. The compilation of the source file fails with the following error: 'svg_color_constant' unknown identifier in file svg_color.hpp @ line37 Did I miss something? Best regards, Marc Viala > -----Message d'origine----- > De : boost-bounces(a)lists.boost.org > [mailto:boost-bounces@lists.boost.org] > De la part de Paul A. Bristow > Envoyé : jeudi 5 février 2009 10:35 > À : boost(a)lists.boost.org > Objet : Re: [boost] [SVG Plot] What happened to this library? > > > -----Original Message----- > > From: boost-bounces(a)lists.boost.org [mailto:boost- > bounces(a)lists.boost.org] > On > > Behalf Of Joel > > Sent: 04 February 2009 23:45 > > To: boost(a)lists.boost.org > > Subject: [boost] [SVG Plot] What happened to this library? > > > > Paul A. Bristow <pbristow <at> hetp.u-net.com> writes: > > > 3 I am close to updating the documentation (and enhanced code) > > > for the > GSoC > > > 2007 SVG plot project by Jake Voytko - including Doxygenation and > > > John Maddock's auto indexing. The code is in a useful (but > > > unpolished) state > and > > > I am confident it will allow neat graphs to display data like > time_series > > > with minimal programming effort. The SVG files produced are tiny, but > high > > > quality, and can be viewed with quality browsers. > > > Is there a URL for this current version of the code? A quick look > > on > google > > only found me Jake's site which is from August 2007: > > > > http://www.jakevoytko.com/code.php > > That is way out of date. > > There is the latest version on SVN > > https://svn.boost.org/svn/boost/sandbox/SOC/2007/visualization/ > > but I am still actively working on it (especially the docs) so use at > your own risk (peril even!). > > Feedback welcome of course. > > > Also, will there be boost graph support? > > Not unless you provide it ;-) > > Paul > > --- > Paul A. Bristow > Prizet Farmhouse > Kendal, UK LA8 8AB > +44 1539 561830, mobile +44 7714330204 > pbristow(a)hetp.u-net.com > > > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost

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ASIO sockets and stream buffers
by Jeff Diewald 05 Feb '09

05 Feb '09

I'm having trouble with trying to connect my TCP sockets up to a stream buffer, and need some help. I've already opened my sending socket, or accepted a connection to get a new receiving socket, and I want to send messages back and forth. What I'd like to write is something like: void sendMessage(boost::asio::ip::tcp::socket* s) { ?? some stream type ?? str(s); str << ... write stuff ... << flush(); str >> ... read stuff ...; } I can't seem to find the right stream type that takes my existing socket. Does such a creature exist in the ASIO library? Help! Thanks in advance, Jeff Diewald JEOL USA

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Re: [Boost-users] boost and std collisons in c++0x
by Daniel Lidström 05 Feb '09

05 Feb '09

Hello, here is how I have solved this problem where I work: Create a header for each class that you want to use, that exists in both boost and std::tr1. For example, here's our local shared_ptr.h: #if !defined(SHARED_PTR_H__20080527T1436) #define SHARED_PTR_H__20080527T1436 #if defined(_MSC_VER) && _MSC_VER>=1500 && defined(_HAS_TR1) // Visual Studio 2008 TR1 version #include <memory> namespace GFLUtils = std::tr1; #else // Boost version #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> namespace GFLUtils = boost; #endif #endif If you also have to rely on VC6 (as we do) then you can't selectively import parts from a namespace (using boost::shared_ptr doesn't work). But if you only use more modern compiler, you can do this: #if !defined(SHARED_PTR_H__20080527T1436) #define SHARED_PTR_H__20080527T1436 #if defined(_MSC_VER) && _MSC_VER>=1500 && defined(_HAS_TR1) // Visual Studio 2008 TR1 version #include <memory> namespace GFLUtils { using std::tr1::shared_ptr; using std::tr1::enable_shared_from_this; } #else // Boost version #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> namespace GFLUtils { using boost::shared_ptr; using boost::enable_shared_from_this; } #endif #endif Hope this helps! Regards, Daniel Lidström Stockholm, Sweden _____ From: Ein Held [mailto:held_ein@yahoo.de] Sent: Wednesday, February 04, 2009 1:23 PM To: boost-users(a)lists.boost.org Subject: [Boost-users] boost and std collisons in c++0x Hello I would like to know more about boost's general attitude towards c++0x and the collisions of boost with std. As of now, we move both, ::boost- and ::std-namesspace in the global namespace via using xxx. This is exactly what we want - boost and the stl are both such fundamental libraries that using an explicit namespace specifier everytime we want to use content of these namespaces is not accaptable. This would just blow the code and make it unreadable. Once we move up to c++0x, we will not be able to keep this way of coding up. ::std::tr1 is merged into ::std and so the former tr1 classes will collide with the boost ones if explicit namespace identifiers are missing. I would like to stress the fact that code, perfectly fine to the boost documentation, will fail to compiler most likely. #include <iostream> //This one might include <array> using namespace std; #include <boost/array.hpp> using namespace boost; array<int,1> blub; //fail Is there anything planned to prevent this happen? Thank you

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[Accumulator] Build error in using BOOST::accumulator on WXP VC8
by dhruva 05 Feb '09

05 Feb '09

Hello, I am using BOOST::accumulator from 1.37. I get the following warning in the build on WXP using VC8 (MSVC 2005). I am exploring to find out where the problem could be, posting to find is someone has experienced this problem. Since our build treats warnings as errors, I am stuck. ...include\boost/fusion/container/vector/detail/deref_impl.hpp(46) : warning C4003: not enough actual parameters for macro 'index' -dhruva -- Contents reflect my personal views only! Add more friends to your messenger and enjoy! Go to http://messenger.yahoo.com/invite/

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[Python] Expose c++ instances to python
by Germán Diago 05 Feb '09

05 Feb '09

Hello. I'm trying to embed python to an application. I did that with success and I'm using boost.python to make some bindings to my API. What I would like, is that the interpreter has access to my objects at runtime, namely, I don't want to create objects from python code but to use the c++ objects, created in my c++ application, from python (and I have wrappers for those in boost.python). I don't know how to achieve this. I just know how to wrap classes, but I have no idea how to expose instances. Any idea how to achieve this? I googled and found nothing clear. Thanks in advance.

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[serialization] Sending user data to serialize()?
by Robert Dailey 04 Feb '09

04 Feb '09

Hi, I have a complex case I'm trying to work with. I may be doing this completely wrong so if there is a better design for this I'm always open for that. However for now I'm going to assume my particular problem can be solved. There exists two classes: A and B. Class A is defined as such: class A { public: template< typename Archive > void load( Archive& archive, unsigned int ) { archive & m_listOfB; } private: std::vector<int> m_listOfInt; boost::ptr_vector<B> m_listOfB; }; And class B is defined roughly as: class B { public: template< typename Archive > void load( Archive& archive, unsigned int ) { // Code isn't important here } }; Here's the problem: For each B that is deserialized by A::load(), I need to pass in a reference to m_listOfInt. So, essentially the load() function in B would look something like this: void load( Archive& archive, unsigned int, std::vector<int>& listOfInt ) { } I was hoping boost.bind could be used somewhere, but I just don't see how. One way to solve the problem is to call B::load() explicitly with the extra parameter, but I don't think that's an appropriate solution. Any ideas on how to solve this? Or perhaps I'm trying to solve the wrong problem.

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[boost.asio] repeating a timer
by Sean Farrow 04 Feb '09

04 Feb '09

Hi: I've just been looking at the boost asio timers, I was wondering whetherthere is a repeat timer, so that my call back will be executed everytime the timer completes. This needs to execute more than once. Any help apreciated. Sean.

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Finding the n smallest items in a list
by Ruediger Berlich 04 Feb '09

04 Feb '09

Hi there, I'm searching for a method to find the n smallest numbers in a list of m >> n numbers. The n numbers need to be sorted. m will usually be in the range of 100-1000, n will be 5 or less. So far I'm simply sorting the entire vector, which I assume is not very efficient, as the other m-n items in the container can remain unsorted. Is there a function in Boost that can help me in this situation ? Best Regards, Ruediger

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[date_time] posix_time::time_duration::operator<< fails for hours>23
by Soren Dreijer 04 Feb '09

04 Feb '09

I'm creating a posix_time::time_duration object based on the minutes() helper function. If I specify a large value, such as 2000, I get a time_duration of 33:20:00. Take a look at the following piece of code, though: time_duration td = minutes(2000); cout << to_simple_string(td); // OK cout << td; // Fails with an assertion in VS2008 The latter call fails with the following assertion in strftime.c on line 658: _VALIDATE_RETURN( ( ( timeptr->tm_hour >=0 ) && ( timeptr->tm_hour <= 23 ) ), EINVAL, FALSE) Apparently, operator<< expands to _expandtime(), which doesn't allow values for the hour to be greater than 23. Is this intended behavior, or should I just always use to_simple_string() rather than the convenient operator<< ?

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[asio] how to handle sync_accept error to avoid server hang on?
by tomasz jankowski 04 Feb '09

04 Feb '09

hello, actualy I'm testing my server. I'm making new connections faster than server is able to handle it. because of it server quickly is getting from system errno 24 (Too many open files). because of chaining async operation in asio design async_accept handler like below lead to server hang on. void AnldServer::handle_accept(const boost::system::error_code& e) { if (!e) { new_connection_->start(); new_connection_.reset(new AnldConnection(io_service_, request_handler_)); acceptor_.async_accept(new_connection_->socket(), boost::bind(&AnldServer::handle_accept, this, boost::asio::placeholders::error)); }else{ NDSLOG_NOTICE_S() << "Accept error: " << e << "\n"; } } Since we are not starting a new accept operation the io_service will run out of work to do and the server will hang on (if it was daemonised) or exit(if not). ofcourse server in production environment couldn't behaves like this. server must can handle such situation. my question is: how to fix it? just start async_accept without creating new_connection in case of error? like this for example? void AnldServer::handle_accept(const boost::system::error_code& e) { if (!e) { new_connection_->start(); new_connection_.reset(new AnldConnection(io_service_, request_handler_)); acceptor_.async_accept(new_connection_->socket(), boost::bind(&AnldServer::handle_accept, this, boost::asio::placeholders::error)); }else{ NDSLOG_NOTICE_S() << "Accept error: " << e << "\n"; acceptor_.async_accept(new_connection_->socket(), boost::bind(&AnldServer::handle_accept, this, boost::asio::placeholders::error)); } } I have just tested above code - it seems to work fine. but maybe someone have beter solution> or maybe it is good idea to add sleep(5) before async_accept in case of error? thanks, tom ---------------------------------------------------- Twoja rodzina na bliscy.pl Zobacz: http://klik.wp.pl/?adr=http%3A%2F%2Fcorto.www.wp.pl%2Fas%2Fbliscy.html&sid=…

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What does sys_err = 3 mean? or where can I find out?
by Andrew Bond 04 Feb '09

04 Feb '09

I am using Boost filesystem and I am getting an error (sys_err = 3). Where can I find a human-readable explanation of this error? Are there text explanations that can be included in my app to better inform the end user what the erro means? Any help will be much appreciated. Andrew Bond

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Boost compatibility with Green Hills Integrity RTOS and Windows CE
by Vikas Goel 04 Feb '09

04 Feb '09

Hi, I am planning to use Boost libraries with Green Hills Integrity RTOS and Windows CE. Please let me know if there are any known issues (like build, compilation, etc) in running Boost on Green Hills Integrity RTOS and Win CE. Any comment regarding usage of Boost with any other RTOS is also welcome. Thanks & Regards, Vikas **************** CAUTION - Disclaimer ***************** This e-mail contains PRIVILEGED AND CONFIDENTIAL INFORMATION intended solely for the use of the addressee(s). If you are not the intended recipient, please notify the sender by e-mail and delete the original message. Further, you are not to copy, disclose, or distribute this e-mail or its contents to any other person and any such actions are unlawful. This e-mail may contain viruses. Infosys has taken every reasonable precaution to minimize this risk, but is not liable for any damage you may sustain as a result of any virus in this e-mail. You should carry out your own virus checks before opening the e-mail or attachment. Infosys reserves the right to monitor and review the content of all messages sent to or from this e-mail address. Messages sent to or from this e-mail address may be stored on the Infosys e-mail system. ***INFOSYS******** End of Disclaimer ********INFOSYS***

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[signals (thread safe)] Scope of slot_call_iterator (or how to implement deferred signals)
by Fabio Fracassi 04 Feb '09

04 Feb '09

Hi, I am currently trying to implement deferred signals using boost signals (well thread safe signals). I had the (crazy?) idea that it might be possible to hijack the combiner interface to do this. The design rational said that during the signal call the state (including the arguments that were passed) are cached for the combiner. So, what I tried to do was to copy and store the first and last iterater out of the combiner, to iterate over them at a later time, to call the slots. What I don't know is whether the slot_call_iterator (and the data it uses ) stays in scope after the signal call (i.e. signal...::operator() ) returns. Here is what I tried: #include <boost/signal.hpp> #include <boost/tr1/memory.hpp> #include <queue> struct signal_queue { signal_queue() : m_signals() {} template <typename InputIterator> void add_signal(InputIterator first, InputIterator last) { m_signals.push( std::tr1::shared_ptr<sig_iterator_range_placeholder>( new sig_iterator_range_holder<InputIterator>(first, last))); } bool process_one_signal() { if (!m_signals.empty()) { std::tr1::shared_ptr<sig_iterator_range_placeholder> sig = m_signals.front(); m_signals.pop(); sig->send(); return true; } return false; } private: struct sig_iterator_range_placeholder { virtual void send() = 0; }; template <typename InputIterator> struct sig_iterator_range_holder : sig_iterator_range_placeholder { sig_iterator_range_holder( InputIterator first, InputIterator last) : m_first( first ), m_last( last ) {} virtual void send () { while (m_first != m_last) { *m_first++; } return; } private: InputIterator m_first; InputIterator m_last; }; std::queue< std::tr1::shared_ptr<sig_iterator_range_placeholder> > m_signals; }; struct defered_send { typedef void result_type; template<typename InputIterator> void operator()(InputIterator first, InputIterator last) const { s_signalQueue.add_signal( first, last ); } static signal_queue s_signalQueue; }; signal_queue defered_send::s_signalQueue = signal_queue(); // Tests struct test_slots { void operator()() const { std::cout << "exec Slot()" << std::endl; } void operator()(int t1, int t2) const { std::cout << "exec Slot(" << t1 << ", " << t2 << ")" << std::endl; } }; int main () { boost::signal<void ( int, int ), defered_send> def_ii; test_slots test; def_ii.connect(test); std::cout << "Send Defered Signals ... " << std::endl; def_ii(42, 24); // <- Point 1 std::cout << "Entering 'event loop' ... " << std::endl; while ( defered_send::s_signalQueue.process_one_signal() ) {} std::cout << "Done." << std::endl << std::flush; return EXIT_SUCCESS; } The good news is that it doesn't crash, though I suspect that this is pure luck. After the slot call (Point 1) some things go out of scope (most notably the cache variable in slot_call_iterator). Now to make a long story short. Is what I am trying to do possible? If not should it? Or do I have to find another way to achive this? If so does someone have a hint? Regards Fabio

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Re: [Boost-users] Transferring files across a network.
by Andrew Maclean 04 Feb '09

04 Feb '09

To all those who helped, especially Rahul who very kindly made some sample code available and put me on the right track. I now have a client and a server that can handle multiple files being sent over the network. The files are attached for your interest. If anyone can improve them I really will welcome their comments. If there is a need, it is Ok to include them as examples in the ASIO documentation. I have no issues with this. Thanks once again to everyone who helped. Regards Andrew

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Problem transforming a vector<bool> to a vector<any>
by Fabrice_CBA 04 Feb '09

04 Feb '09

Hi everyone, I am working on a project in which I'm using a "simplified" version of the boost::any library. By simplified, I mean that I got rid of the #defines and made it independent from the rest of boost. The changes are very small, and in my opinion shouldn't impact much the class, since the general structure is still there. My implementation is attached to this message. http://www.nabble.com/file/p21822878/Any.h Any.h However I am having a problem transferring a vector<bool> into a vector<any>. It works for any other types I've tested, only booleans fail. Here is an example: std::vector<std::string> source0(1, "SomeString"); std::vector<long> source1(1, 666); std::vector<bool> source2(1, true); std::vector<double> source3(1, 6.66); std::vector<any> destination; destination.push_back(source0[0]); destination.push_back(source1[0]); destination.push_back(source2[0]); destination.push_back(source3[0]); When checking what is in destination[2], it seems it only holds {...}, and not the original {true}. Whereas it works perfectly for the other values. Any idea on what I'm doing wrong? Any help appreciated. Thanks, Fabrice -- View this message in context: http://www.nabble.com/Problem-transforming-a-vector%3Cbool%3E-to-a-vector%3… Sent from the Boost - Users mailing list archive at Nabble.com.

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How to convert boost::posix_time::ptime to FILETIME structure?
by Archie14 03 Feb '09

03 Feb '09

Is there any helper function to convert boost::posix_time::ptime to FILETIME? I am trying to pass datetime value from boost-based app to another (C#). Looks like that FILETIME (that can be represented as long) is a good option, besides string. May be there is better alternative?

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Nullary metafunction
by er 03 Feb '09

03 Feb '09

Hi All, I'm looking for template<typename> class F such that F<T>::type is T::type if it exists, T itself otherwise. I was hoping apply<T>::type would work, by analogy with the well known example apply<std::vector<_>,X>::type, but apparently not.

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