January 2010 - Boost-users - lists.preview.boost.org

[boost::function] Is there a way to assign a generic function, regardless number of parameters?
by Matheus Araújo Aguiar 29 Jan '10

29 Jan '10

Hello list, My doubt is simple. We need to implement some callbacks, but we don't want to declare a boost::function to every different callback, we just want to declare one generic boost::function to receive any function, with any number of parameters (the return type may be one well defined, no problem with that in our case). Is there a way to do this? What we want to do is something like is done in the asynchronous methods of boost::asio when passing the callback to the async operation. TIA, -- Matheus Araújo Aguiar Computer Scientist matheus.pit(a)gmail.com

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[UTF] Provide a custom init_unit_test
by Ahmed Badran 29 Jan '10

29 Jan '10

Hi, I have a single test module (defined via BOOST_TEST_MODULE), then multiple test suites, each defined in its own .cpp file and I am using a single header variant of the unit test framework. Is there an easy way to provide my own init_unit_test and have it plug into the rest of the system, with main and everything else provided by the utf library? I've looked at the headers of utf and it seemed that the generation of main and other initialization routines are tied to also providing an "init_unit_test" which causes a multiple definition problem at link stage. Regards, Ahmed

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Operator overloading of a class template in a namespace
by Surya Kiran Gullapalli 29 Jan '10

29 Jan '10

Hello all, Let me give you a heads up first. This is a general c++ question. not a boost one. But posting it here as we've C++ gurus out there. I've this piece of code http://paste.pocoo.org/show/171324/ The code fails to compile when *St.1 *is uncommented. I read some documents on operator overloading and namespaces and moved the output operator into the same namespace as the class (skg). This works fine. But my question is different. If the output operator is in global namespace and class in skg namespace *St. 2 * (cout statement) works fine, but not the copy statement. Why ? Thanks in advance, and apologies for offtopic. Surya

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Re: [Boost-users] [multi_array] compiling and changing an example
by Steven Watanabe 29 Jan '10

29 Jan '10

AMDG sean farrow wrote: > I'm trying to use boost::multi_array, I've included boost/multi_array.hpp > in the file and have the following code: > > private: > > typedef boost::multi_array<double, 3> array_type; > > typedef array_type::index index; > > array_type test(boost::extents[3][4][2]); > > Commenting out the third line compiles fine, but leaving this in gives a > c2061 error. It seems there is an issue with boost::extents, which header > is this in? I don't have a using boost; earlier, should I have? I'm using > visual c+ 2008. > It compiles fine for me with the trunk: #include <boost/multi_array.hpp> int main() { typedef boost::multi_array<double, 3> array_type; typedef array_type::index index; array_type test(boost::extents[3][4][2]); } What version of boost are you using? What is your code exactly (with #includes)? What is the exact error message? In Christ, Steven Watanabe

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The Boost difference b/w 32 and 64 bits
by JongKwan Kim 29 Jan '10

29 Jan '10

Hello, I am running my own C and C++ code using the Boost Library. First, I run the my code with Boost Library 1.36.0 on the 32 bits linux (Ubuntu) computer, so it is working well. However, I need to move the same code on the 64 bits linux (RedHat) computer. So, I am trying to run the code with Boost Library 1.41.0 on the 64 bits linux machine. At that time, the compiling is well, but when I run it, there is segmentation fault. I do not know if the problem is because of the difference between 32 bits and 64 bits or between 1.36.0 and 1.41.0 versions. Could you guys please let me know what is problem? When I type "make install" on the prompt window, I got messages like below.... ............................. /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libz.a(crc32.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_atan.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_cos.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_sin.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_exp.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_fmod.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_log.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_log10.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_pow.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_sqrt.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_round.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(m_isnan.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(m_finite.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_ceilf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_cosf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_floorf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_sinf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_expf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_fmodf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_logf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_log10f.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_powf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(w_sqrtf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_roundf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(m_isnanf.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(m_finitef.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(k_standard.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_lib_version.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_matherr.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(e_exp.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(e_fmod.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(e_log.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(e_log10.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(e_pow.o)' is incompatible with i386:x86-64 output /usr/bin/ld: warning: i386 architecture of input file `/usr/lib/libm.a(s_rint.o)' is incompatible with i386:x86-64 output ...............etc............. Thanks,

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[Boost Circular Buffer] Warning C4099 when compiling with boost/circular_buffer.hpp
by Lloyd Zslnka 28 Jan '10

28 Jan '10

Boost Version: 1.35.0 Compiler: Visual Studio 2008 Version 9.0.30729.1 SP OS: Windows XP SP3 Hello, I'm compiling boost/circular_buffer.hpp with my project and am getting the following warning message: ...\boost\boost_1_35_0\boost\circular_buffer\base.hpp(180) : warning C4099: 'boost::cb_details::iterator' : type name first seen using 'class' now seen using 'struct' ...\boost\boost_1_35_0\boost\circular_buffer\details.hpp(187) : see declaration of 'boost::cb_details::iterator' ...\boost\boost_1_35_0\boost\circular_buffer\base.hpp(2477) : see reference to class template instantiation 'boost::circular_buffer<T,Alloc>' being compiled In looking at details.hpp, I see that iterator is declared as a class on line 187, but in base.hpp it is declared as a struct on line 180. Is this a mistake or am I missing something? Thanks, Lloyd --------------------------------------------------------------------- This transmission (including any attachments) may contain confidential information, privileged material (including material protected by the solicitor-client or other applicable privileges), or constitute non-public information. Any use of this information by anyone other than the intended recipient is prohibited. If you have received this transmission in error, please immediately reply to the sender and delete this information from your system. Use, dissemination, distribution, or reproduction of this transmission by unintended recipients is not authorized and may be unlawful.

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Boost, bjam, and symbolic links
by svdbg＠free.fr 28 Jan '10

28 Jan '10

Hello, I generated some Boost librairies with bjam, and I get many symbolic links. For date_time : libboost_date_time-gcc41-mt-1_39.a libboost_date_time-gcc41-mt-1_39.so -> libboost_date_time-gcc41-mt-1_39.so.1.39.0 libboost_date_time-gcc41-mt-1_39.so.1.39.0 libboost_date_time-gcc41-mt.a -> libboost_date_time-gcc41-mt-1_39.a libboost_date_time-gcc41-mt.so -> libboost_date_time-gcc41-mt-1_39.so.1.39.0 Why don't I just get the .a and .so ? Why these 3 symbolic links ? And why do the original files have a so complicated name for the .so, with the release version mentionned twice ? Isn't it possible to just have : libboost_date_time-gcc41-mt-1_39.a libboost_date_time-gcc41-mt-1_39.so Thanks for help. I don't know what to do of these symbolic links. Note : I am a newbie in Linux.

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[Boost.Thread]
by Andrew Chinkoff 28 Jan '10

28 Jan '10

Hi. There is a test program I would to be explained to me: *** BEGIN OF TEST PROGRAM *** #include <stdio.h> #include <boost/thread.hpp> #define USE_SPINLOCKS //#define USE_MUTEXES boost::thread th1; boost::thread th2; boost::mutex mutex; int global_int = 0; bool IsNotEven(int code) { boost::mutex::scoped_lock locker(mutex); bool ret = (code & 1); return ret; } void thread_func() { for(int i = 0; i < 1000000; ++i) { #ifdef USE_MUTEXES if(IsNotEven(global_int)) // (1) #elif defined USE_SPINLOCKS if(__sync_fetch_and_and(&global_int, 1)) // (2) #else ERROR__WRONG_COMPILED; #endif global_int+=9; else global_int+=1; } } int main() { th1 = boost::thread(&thread_func); th2 = boost::thread(&thread_func); th1.join(); th2.join(); printf("global_int = %d\n", global_int); return 0; } *** END OF TEST PROGRAM *** Results of test program: 1) Test program compiled with USE_SPINLOCKS. Outputs are always: "global_int = 10" "global_int = 10" "global_int = 10" 2) Test program compiled with USE_MUTEXES. Outputs differ from each other: "global_int = 10000008" "global_int = 10000000" "global_int = 9763210" Could you explain me why outputs produced with USE_SPINLOCKS compilation differ from USE_MUTEXES ones? And what is the difference between (1) and (2) lines? Best, Andrew. P.S.: I use guest Ubuntu-8.04 installed on VirtualBox. Host OS = Vista.

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Problem compiling boost libraries
by Daniel Veneros 28 Jan '10

28 Jan '10

Hi, I´m trying to compile a simple example in NetBeans 6.8 on Solaris platform, the code is: struct shm_remove { shm_remove() { shared_memory_object::remove("MySharedMemory"); } ~shm_remove(){ shared_memory_object::remove("MySharedMemory"); } } remover; //Create a shared memory object. shared_memory_object shm (create_only, "MySharedMemory", read_write); //Set size shm.truncate(1000); //Map the whole shared memory in this process mapped_region region(shm, read_write); //Write all the memory to 1 std::memset(region.get_address(), 1, region.get_size()); //Launch child process std::string s(argv[0]); s += " child "; if(0 != std::system(s.c_str())) return 1; That's it, no big deal, but when I try to build this I receive the error: Undefinded first referenced symbol in file shm_unlink, sched_yield, shm_open Anyone knows how can I fix this?? Thanks!!! Dann

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Program options support for wide char
by Bo Jensen 28 Jan '10

28 Jan '10

Program options::options_description has a output operator for std::ostream, but none for std::wostream (if I am mistaken, please correct me). Shouldn't there be one ? I could surely need one :-) Regards Bo

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