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Trouble using shared_ptr with g++ -O0 and -O2 options
by Bear 08 Dec '04

08 Dec '04

Hello there I'm getting a SIGSEGV when using the boost::shared_ptr in my program and compiling with the g++ -O2 option, whereas if I'm using the g++ -O0 option my programs works the way it should. My program is multi-threaded but to the best of my knowledge it is mutex'ed correctly. I compile my program the following way when using -O2 and -O0 g++ -O0 -ggdb3 -DNDEBUG -DTTSERVER .... g++ -O2 -ggdb3 -DNDEBUG -DTTSERVER .... When I use gdb to step through the program (only with 'n') I go into the shared_count.hpp file when using the -O2 option whereas the version compiled with -O0 disregards this file in gdb. The -O2 version of the program crashes in the file checked_delete.hpp and the member "checked_delete": template<class T> inline void checked_delete(T * x) { // intentionally complex - simplification causes regressions typedef char type_must_be_complete[ sizeof(T)? 1: -1 ]; (void) sizeof(type_must_be_complete); => delete x; } Here's the gdb output: Program received signal SIGSEGV, Segmentation fault. 0x08053370 in boost::detail::sp_counted_base_impl<teamtalk::server::ServerChannel*, boost::checked_deleter<teamtalk::server::ServerChannel> >::dispose() ( this=0x8107170) at checked_delete.hpp:36 (gdb) As I mentioned earlier, the -O0 run without problems. Has anyone experienced similar problems? I'm using Boost 1.31 g++ (GCC) 3.3.2 20031218 (Gentoo Linux 3.3.2-r5, propolice-3.3-7) GNU gdb 6.0 Kind regards Bjoern D. Rasmussen

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simple regex compile error
by Brian Gaber 08 Dec '04

08 Dec '04

I have a very simple regex program that will not compile on AIX using IBM's xlc++ compiler. Here is the program: #include <iostream> // for I/O #include <string> // for string #include <boost/regex.hpp> // for pattern matching using std::cout; using namespace std; using namespace boost; int main() { const string tmp1("abc234tree"); static const regex expression(" \\w+"); cout << regex_match(tmp1, expression) << endl; return 1; } Here is the compile statement: /usr/vacpp/bin/xlc++ -o regex regex.cpp -I /usr/local/include -lboost_filesystem-xlc-1_32 -L/usr/local/lib Here is the compiler error: "/usr/local/include/boost/regex/v4/cregex.hpp", line 75.4: 1540-0063 (S) The text "0x001" is unexpected. "/usr/local/include/boost/regex/v4/cregex.hpp", line 100.4: 1540-0063 (S) The text "0x100" is unexpected. "/usr/local/include/boost/regex/v4/cregex.hpp", line 135.3: 1540-0063 (S) The text "1" is unexpected.

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Unresolved symbols in regex libs on tru64
by Mark Helzer 08 Dec '04

08 Dec '04

Hi, I have several unresolved symbols in a test routine compiled on tru64, using libboost_regex-tru.so. The same routine runs great on linux with libboost_regex-gcc.so. I'm using boost 1.32, cxx version 6.5-041 cxx -o regex regex.o -hidden -lcxxstd -non_hidden -rpath /usr/lib -L/usr/lib -lboost_regex-tru ld: Unresolved: boost::regbase::regbase(void) boost::c_regex_traits<char>::init(void) ... boost::re_detail::c_traits_base::lower_case_map ... boost::c_regex_traits<char>::transform(std::basic_string<char, std::char_traits< char>, std::allocator<char> >&, const std::basic_string<char, std::char_traits<c har>, std::allocator<char> >&) Mark Helzer ADP Dealer Services 2525 S.W 1st Portland, OR. (503) 402-3481

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[review-results] Smart Container Library
by Pavol Droba 08 Dec '04

08 Dec '04

Hi, I hereby announce that the Smart Container library is ACCEPTED into Boost. Congratulations and thanks to Thorsten Ottosen for providing us with this library. Most of the reviewers were in favor of acceptance, but there were several requests for improvements. I have consulted them with Thorsten and he proposed to do following changes. I consider them sufficient for acceptance. 1. add support for boost.range in insert functions, constructors etc 2. use void* implementation 3. improve docs as discussed during the review 4. add support for null values: - remove preconditions - add functions is_null( size_t idx ); is_null( iterator ); 5. add more debug checks after access to ptr_begin(), ptr_end() 6. reconfigure policies: ptr_vector<T,clone_manager> becomes ptr_vector<T,clone_allocator = something, std::allocator<T*> = std::allocator<T*> > or perhaps ptr_vector<T,clone_allocator = something< std::allocator<T* > > 7. improve tests I also suggest, that before the inclusion of the library into the boost distribution, the library should be brought in the discussion to verify, that all issues above have been addressed. Best Regards, Pavol Droba Review Manager

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uBlas, using assign on a symmetric matrix range
by Thomas Lemaire 08 Dec '04

08 Dec '04

dear list, I am using ublas from boost 1.32, gcc 3.3.3, solaris 9 I need to copy some independant submatrix (matrix_range) of a symmetric matrix. I use the assign() method to do so. first, I compile without NDEBUG, and a postcondition check in assignment is not met... Assertion failed in file /usr/local/boost/include/boost/numeric/ublas/matrix_assign.hpp at line 797: equals (m, cm) E: src/slamEkf.cpp:325: std::exception ** std::exception: ** external logic I checked that compiling with NDEBUG the assignement is not correct. If I copy the two submatrix using a stupid for loop, it works... I use the default version of symmetric_matric (lower), and I assign _upper_ part of the matrix. I tried to assign the _lower_ part of the matrix and it works ! nothing in the doc tells that using the assign() functions is different with symmetric_matrix... this problem arises only when assigning a submatrix to another submatrix. When assigning an expression to a submatrix in the _upper_ part of the lower symmetric matrix it works fine. Is it a bug ?? -- thomas

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[Build v2] How-to: Link a CPP target with purify (on Solaris) ?????
by Sylvain, Gregory M 08 Dec '04

08 Dec '04

Hello all, This should be a relatively simple problem, but I haven't figure it out yet either.... In Boost.Build v2, how can you link a C++ program with purify on Solaris ? I assumed it would be something like: sun.link.c++="purify CC" but the link action uses "$(.root)/CC" and not a variable. Do you have to write a new purify.jam Jamrules file to make this happen our is there another variable that needs to be defined ? -- Thanks in advance for any clues... greg

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[BGL]newbie bcc32 5.6.4 dijkstra-example.cpp compilation errors
by Yoshi Fujiwara 08 Dec '04

08 Dec '04

Borland bcc32 5.6.4 (Borland builder 6 updated #4) boost_1_32_0 Being a newbie, i tried to compile dijkstra-example.cpp, an example given in BGL tutorial, but got the following compilation errors (message truncated somewhat). bcc32 -w- dijkstra-example.cpp Borland C++ 5.6.4 for Win32 Copyright (c) 1993, 2002 Borland dijkstra-example.cpp: E2406 C:\include\boost/property_map.hpp 25: Dependent type qualifier 'int *' is not a class or struct type E2406 C:\include\boost/property_map.hpp 26: Dependent type qualifier 'int *' is not a class or struct type E2406 C:\include\boost/property_map.hpp 27: Dependent type qualifier 'int *' is not a class or struct type E2406 C:\include\boost/property_map.hpp 28: Dependent type qualifier 'int *' is not a class or struct type E2451 C:\include\boost/graph/dijkstra_shortest_paths.hpp 243: Undefined symbol max( ... E2285 C:\include\boost/graph/dijkstra_shortest_paths.hpp 243: Could not find a match for 'choose_param<P,Default>(error_property_not_found,undefined)' ... E2285 C:\include\boost/graph/dijkstra_shortest_paths.hpp 245: Could not find a match for 'choose_param<P,Default>(error_property_not_found,undefined)' ... E2285 C:\include\boost/graph/dijkstra_shortest_paths.hpp 247: Could not find a match for 'dijkstra_shortest_paths<VertexListGraph,Param,Tag,Rest>( ... *** 8 errors in Compile *** It seems that this may be FAQ, but i could not find any answer to such posts as [BGL]bellman_ford_internet example by Kaled Ahmed [BGL]DIJKSTRA - ospf-example by Khaled Saleh i appreciate advice from bcc32 5.6.4 users who are doing well with it. best wishes, Yoshi

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RE: Re: Re: Compiling boost on tru64 (Richard Hadsell) (Peter Dimov)
by Mark Helzer 07 Dec '04

07 Dec '04

>Mark Helzer wrote: >> >>Kewl, that works, I got a little further down the path. Next problem: >> >> cxx: Error: /adp/local/src/boost_1_32_0/boost/bind.hpp, line 206: #266 >> "value" is ambiguous > >Can you please try adding _bi:: in front of value and see if this fixes the problem? Success! I added the "_bi::" at lines 206 & 208 of boost/bind.hpp & the compile was successful.

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FW: VS 7.1 and boost-1_32 serialization error LNK2019: unresolved external symbol
by Holmes, Michael A (Mike) 07 Dec '04

07 Dec '04

> I have just installed the latest boost library and managed to run the > serialization demo from the included VS7 project. However being a > skeptic I thought I would build the demo myself before committing to a > real use of the library. I made a new win32 console application and > pasted in the serialization demo.cpp code and it fails with errors > like the one shown. > > boostTest1.obj : error LNK2019: unresolved external symbol "public: > __thiscall boost::archive::basic_text_oprimitive<class > std::basic_ostream<char,struct std::char_traits<char> > > >::~basic_text_oprimitive<class std::basic_ostream<char,struct > std::char_traits<char> > >(void)" > (??1?$basic_text_oprimitive@V?$basic_ostream@DU?$char_traits@D@std@@@s > td@@@archive@boost@@QAE@XZ) referenced in function "public: virtual > __thiscall boost::archive::text_oarchive_impl<class > boost::archive::text_oarchive>::~text_oarchive_impl<class > boost::archive::text_oarchive>(void)" > (??1?$text_oarchive_impl@Vtext_oarchive@archive@boost@@@archive@boost@ > @UAE@XZ) > > I did make sure that > "c:\boost\include\boost-1_32" is in the Tools - options - projects - > vc++ directories - include files > "C:\boost\lib" is in the Tools - options - projects - vc++ > directories - library file And I included "C:\boost\lib" explicitly for the project > I have been looking for the answer with Google search for a couple of > hours, it must be something stupid on my part, any pointers > appreciated. > Thanks Mike >

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serialization library - reloading objects
by Sergey Skorniakov 07 Dec '04

07 Dec '04

Hello, All! Are there any way to load existing objects by base class pointer without creating new? Examination of input archives source code does not give me any idea how I can achieve it. I think I need some mechanism for runtime switching archive object tracking behaviour in that way so all objects will interpreted as already created (or per-object tracking registration without actual object loading to pre-register pointer to object as already created before object loading). With best regards, Sergey.

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building boost with dev-cpp
by Katti Faceli 07 Dec '04

07 Dec '04

Hi, I need some help on building boost. I am trying to build boost 1.32.0 with dev-cpp. I am employing the command line: bjam "-sTOOLS=mingw" "--with-python-root=C:\Python24" "-sMINGW_ROOT_DIRECTORY=C:\Program Files\Dev-Cpp" install And I am getting the errors: D:\katti\programasOutros\bibliotecasC++\boost\boost_1_32_0>bjam "-sTOOLS=mingw" "--with-python-root=C:\Python24" "-sMINGW_ROOT_DIRECTORY=C:\Program Files\Dev-Cpp" install ...found 11553 targets... ...updating 1601 targets... gcc-C++-action bin\boost\libs\date_time\build\boost_date_time.dll\mingw\debug\gr eg_month.obj In file included from D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0 /boost/config.hpp:40, from D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0 /boost/date_time/constrained_value.hpp:12, from D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0 /boost/date_time/gregorian/greg_month.hpp:12, from D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0 /libs/date_time/src/gregorian/greg_month.cpp:14: D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0/boost/config/select_s tdlib_config.hpp:20:19: utility: No such file or directory In file included from D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0 /boost/shared_ptr.hpp:26, from D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0 /boost/date_time/gregorian/greg_month.hpp:14, from D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0 /libs/date_time/src/gregorian/greg_month.cpp:14: D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0/boost/detail/shared_c ount.hpp:34:61: memory: No such file or directory D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0/boost/detail/shared_c ount.hpp:35:41: functional: No such file or directory D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0/boost/detail/shared_c ount.hpp:36:46: exception: No such file or directory D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0/boost/detail/shared_c ount.hpp:37:46: new: No such file or directory D:/katti/programasOutros/bibliotecasC++/boost/boost_1_32_0/boost/detail/shared_c ount.hpp:38:61: typeinfo: No such file or directory ....

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Boost Python installation Windows XP+Visual C++ 7.1
by Nguyen Xuan Son 07 Dec '04

07 Dec '04

Hi, My problem is the following 1/ I install Python 2.4 at D:\Programs\Python24 using the binary file from www.python.org 2/ following the document from the boost.org I type the command >bjam "-sTOOLS=vc-7_1 --with-python-root=D:\Programs\Python24" stage But I receive the following error > --with-python-root=D:\Programs\Python24-tools.jam: Invalid argument I think I do something wrong here. If I use the simple command >bjam "-sTOOLS=vc-7_1 " stage I get the message: >skipping Boost.Python ..... Can someone show me how can I install Boost.Python correctly? Thanks Xuan Son

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Re: Re: [Boost-users] lu.hpp : permutation matrix error
by Daniel L Elliott 07 Dec '04

07 Dec '04

------------------------------ Toon Knapen wrote: This is again the old include-policy problem. Previously the headers of ublas were not self-contained. This has been fixed but only on a branch (and thus not in the 1.32 release). I plan to merge this branch also to the HEAD. For now, you just need to include storage.hpp before you include lu.hpp. In that case, on line 24 of lu.hpp will it recognise unbounded_array (which is defined in storage.hpp) ------------------------------ Toon, Thank you for the response! I was unaware of this include-policy problem. Will you be merging this code soon? I will try to look for your email about this merge. I tried fixing this within lu.hpp and it appeared as if errors were being added recursively so I gave up and posted the question. Since adding #include<storage.hpp> to lu.hpp didn't fix the problem, should I expect to have to include additional files to my code to fix errors in files such as storage.hpp? Thanks again for your time and effort, - dan elliott

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Re: [BUG] Missing method in gregorian::greg_year
by Bart 07 Dec '04

07 Dec '04

On Mon, 06 Dec 2004 12:59:01 -0500, Joel Reed wrote: > the class gregorian::greg_year in the date_time library is missing a method > implemented in greg_day and greg_month. > > the method is: > > unsigned short as_number() const {return value_;} > > i checked cvs, on 12/6/04, to confirm this is still an issue. > http://cvs.sourceforge.net/viewcvs.py/boost/boost/boost/date_time/gregorian… > > we have been very impressed with this library and wanted to report > this minor inconsistency as a small, small way to say thanks. > > jr greg_year shouldn't need an as_number function. It's a constrained unsigned short with a min of 1400 & a max of 10000. The as_number function was added to greg_month and greg_day to ease math operations. Since greg_year is a constrained value math simply "works", as does operator<<. Is there a specific reason why you'd like one added to greg_year? Thx, Bart

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Re: boost filesystem path question
by Surya Kiran Gullapalli 06 Dec '04

06 Dec '04

>> Maybe it isn't the backslash that is causing the problem. What exactly is >> the value of path_from_fs_dialog::string()? >> >> --Beman Well, path_from_fs_dialog::string () some thing like "C:\ProgramFiles \MicrosoftVisualStudio" --Surya

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RE: Boost-users Digest, Vol 389, Issue 2
by Mark Helzer 06 Dec '04

06 Dec '04

Today's Topics: 9. Re: Re: Newbie using regex libraries (John Maddock) (Caleb Epstein) ------------------------------ Message: 9 Date: Sat, 4 Dec 2004 19:35:00 -0500 From: Caleb Epstein <caleb.epstein(a)gmail.com> Subject: Re: [Boost-users] Re: Newbie using regex libraries (John Maddock) To: boost-users(a)lists.boost.org Message-ID: <989aceac04120416352e161707(a)mail.gmail.com> Content-Type: text/plain; charset=US-ASCII On Fri, 3 Dec 2004 09:25:16 -0800, Mark Helzer <mark_helzer(a)adp.com> wrote: > No, they are not. Although that is what I would have expected... > -rwxr-xr-x 1 eoapi clients 4976367 Apr 22 2004 > libboost_regex-gcc-mt-d-1_31.so.1.31.0 > -rwxr-xr-x 1 root root 629005 Jun 29 06:16 > libboost_regex-gcc.so > > I shall clean it up and try rebuilding Note that one of these is for use with multi-threaded builds (-mt) and one is for single-threaded. Depnding on how you're compiling your code, this may explain the linker error. I rebuilt (and downloaded 1.32 along the way) and now libboost_regex-gcc.so is a hard link to libboost_regex-gcc-1_32.so.1.32.0. I don't believe it was before (could be wrong) Anyway, compiling with the generic name now works great, thanx.

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Compiling boost on tru64
by Mark Helzer 06 Dec '04

06 Dec '04

Hi, I'm getting this error trying to build boost tru64cxx65-C++-action bin/boost/libs/date_time/build/libboost_date_time.so/tru64 cxx65/debug/greg_month.o cxx: Error: /adp/local/src/boost_1_32_0/boost/cstdint.hpp, line 87: #5 could not open source file "inttypes.h" Quite true, it doesn't exist. Here's my command line: bjam -sTOOLS=tru64cxx65 install Compiler is >cxx -V Compaq C++ V6.5-041 for Digital UNIX V4.0F (Rev. 1229) Compiler Driver V6.5-041 (cxx) cxx Driver Is this a configuration issue? Mark Helzer ADP Dealer Services 2525 S.W 1st Portland, OR. (503) 402-3481

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[Review Results] Named Parameters Library
by Doug Gregor 06 Dec '04

06 Dec '04

The Named Parameters Library has been accepted into Boost. Congratulations to the authors, David Abrahams and Daniel Wallin. The vast majority of reviews were positive, although most reviewers requested additional documentation. Here is a list of the most important/commonly-requested changes or additions to the library: - More documentation! Specifically, + Automatic overload generation should go into the tutorial + Document operator, + Performance data (what's the cost?) + Reference section + "Best practices" section. - Add a metafunction for getting the type of a parameter, e.g., param_type<Params, width_t>::type. - Add test cases for the automatic overload generation macros. - Fix the BOOST_NAMED_PARAMS_MAX_ARITY bug; Cromwell Enage provided a solution. Doug Gregor Review Manager

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Q: Stopping threads (Win32) or... the mysterious case of the thread with split personality
by Dan Dimerman 06 Dec '04

06 Dec '04

Hello, I would like to ask the group if you know of an efficient and clean way to stop a thread. What I've been using till now was a while loop in the function operator()() given to the boost::thread when created, whose condition was a boolean data member. This boolean was the means to stop the thread, such that when it was turned off, the child thread would exit the while loop and join the main thread. I am seeing now that this data member is being held twice (one copy for the main thread and one copy for the child thread) and there's no synch between the two copies; so when the main thread turns it off / false, the child thread goes on (since its copy is still on / true) and hell breaks loose. I am using VC7 in debug mode, so I started looking for some kind of flag/optimization I might be inadvertently using that makes data members into registers (thus explaining the copies), but couldn't find anything of the sort. Any help will be greatly appreciated... Dan --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com) Version: 6.0.805 / Virus Database: 547 - Release Date: 03-Dec-04

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determining a sensible result type for a function
by Agoston Bejo 06 Dec '04

06 Dec '04

Hi! Let's consider this function object: template<typename TLeft, typename TRight> struct mixed_plus : public binary_function<TLeft, TRight, TLeft> { result_type operator() (first_argument_type left, second_argument_type right) const { return left + right; } };

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get_wider<int, float> == float - what is it called in boost?
by Agoston Bejo 06 Dec '04

06 Dec '04

Hi! I may have posted the first half of this question once, sorry for that! : ) The question in short: which boost library enables me to get the "wider" datatype of two, such that get_wider<int, float>::type will be float, and get_wider<float, int>::type will also be float. Hopefully get_wider<int, string>::type will generate a compile-time error, since the two are not convertible to each other. More verbosely: Let's take a look at this simple functor class: template<typename TLeft, typename TRight> struct mixed_plus : public binary_function<TLeft, TRight, TLeft> // result_type: bad solution! { result_type operator() (first_argument_type left, second_argument_type right) const { return left + right; } }; All is fine if I write this: cout << mixed_plus<float, int>()(5.5, 5) << endl; OUTPUT: 11.5 (as expected) But when I write this: cout << mixed_plus<int, float>()(5, 5.5) << endl; OUTPUT: 10 (as expected but not as intended) I vaguely remember that there is a boost library that is able to generate the "wider" data type of two data type, with the help of which I would be able to have the result_type typedef always the appropriate one.

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lu.hpp : permutation matrix error
by Daniel L Elliott 06 Dec '04

06 Dec '04

Hello, I am completely stumped. Using the cvs head 1.32 version of boost with the following program: #include<lu.hpp> #include<vector.hpp> #include<io.hpp> #include<iostream> using std::cout; using std::endl; using namespace boost::numeric::ublas; int main(){ // create a permutation matrix permutation_matrix<size_t> P( size ); // default contructions gives the identity-permutation cout << P << endl; return 0; } I get the following errors: g++ -c -I. -I/s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas -Wall -g3 -I. -I/s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas -o permutationTest.o permutationTest.cpp In file included from permutationTest.cpp:1: /s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas/lu.hpp:24: error: parse error before `,' token /s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas/lu.hpp:29: error: ` vector_type' is not a class or namespace /s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas/lu.hpp:29: error: ` size_type' is not a class or namespace /s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas/lu.hpp:29: error: ` vector_type' fails to be a typedef or built in type /s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas/lu.hpp:29: error: ISO C++ forbids declaration of `size_type' with no type /s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas/lu.hpp:29: error: template declaration of `typedef int boost::numeric::ublas::size_type' /s/chopin/a/grad/dane/thesis/code/boost-1.32/include/boost-1_32/boost/numeric/ublas/lu.hpp:29: confused by earlier errors, bailing out Any ideas as to what might be wrong here? Thank you. -- dan elliott ************************** Dan Elliott 402-210-6429 (me) or 402-210-6735 (amy) dan_elliott(a)cox.net **************************

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HowTo Iterator Facade
by Duane Murphy 06 Dec '04

06 Dec '04

I am implementing an iterator via iterator facade. The container that the iterator is being used with can only return dereferenced values by value (not by reference). If I implement the dereference() function (for facade) by returning a value (instead of reference) then it appears that the iterator works properly. The most important operation that does _not_ work is that the iterator cannot be used with bind(). (bind cannot be used with non-const return types.) If I change the iterator to return a reference type then the iterator functions still work and so does bind. What is the proper way of implementing an iterator with this limitation so that it works properly with bind? In the past, I keep a mutable value member along with the iterator to store the last dereferenced value. Of course this is fraught with problems. Is there an example iterator that demonstrates the proper way of doing this? Is there some kind of proxy class that can be used to overcome this limitation? Thanks for your help, ...Duane

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boost filesystem path question
by Surya Kiran Gullapalli 05 Dec '04

05 Dec '04

Hi, I've this code, which is supposed to work on both windows and linux OS. I'll get a particular directory/file path from a fileselection dialog, where by i process this path. The question for me, is I'm using the boost::filesystem::path constructor like this. boost::filesystem::path p (path_from_fs_dialog, boost::filesystem::native) ; Its working fine on linux (as the string path_from_fs_dialog contains "/" as directory separator). when comes to windows path_from_fs_dialog contains "\" as the directory separator, and the path constructor is throwing exception. What could have been the reason? I've to change the namecheck function from "native" to "no_check" Any ideas what might have gone wrong? Thanks in advance, Surya

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Pool allocating
by Jean-Eric Cuendet 05 Dec '04

05 Dec '04

Hi, I need the following for our Linux C++ soft: - Create a HeapSpace of FixedSize (say 1Mb) - Allocate FixedSize piece of memory (always alloc 16 bytes from this heap for ex.) - Return NULL if no more space in the HeapSpace - Delete them. - Release the memory when all pieces are deleted Is there a way to do exactly that with Boost? Thanks. -jec

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