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Bind
by Etienne Philip Pretorius 04 May '09

04 May '09

Hello list, Can boost.bind() be used to delay the call to a member function until you have gathered all the data types to populate the function parameter list? Etienne

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thread interrupt does not work on thread proc from dll
by Dan Aragona 04 May '09

04 May '09

I am creating a thread from a static lib, and passing in a thread proc from a dynamic lib. The problem I am having is that the interrupt does not work - join just hangs on the call to WaitForMultipleObjects from within thread.cpp. I can get interrupt to work if my thread proc is from a static lib, but I cannot get it to work if my thread proc is from a dynamic lib. I notice when I step into: bool interruptible_wait() the call if(get_current_thread_data()&&get_current_thread_data()->interruption_enabled) is always false. When I call bool chkInterruptEnabled = boost::this_thread::interruption_enabled(); from within my thread proc it is true from the static lib but false from the dynamic lib. I am using VS2005 sp1 and 1_36 Any help is greatly appreciated.

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Boost Gentoo amd64
by Mark Chandler 03 May '09

03 May '09

Hi, Im trying to run a 32 bit app that uses boost on gentoo 64bit. The problem is that the server is in a secure mode and can only run packages signed by gentoo. The gentoo boost install only has the option of compiling for 64bit (the native os bit size) and i was wondering who i would need to speak to in order to get a 32bit compiling option added. Mark

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Filesystem: Case insensitive search on case sensitive systems
by Chris Spencer 03 May '09

03 May '09

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi all, I am writing a cross-platform program which takes path names from a Windows-originating file. As such, there is no guarantee that the paths match the case of what is actually stored in the file system. Does anyone have any advice on the best way to do a case-insensitive search to get the correct path? Thanks, Chris. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkn+AgoACgkQ6iqRtkAADZhrFQCgxL0prbFme94Y6/D6IqNQccT+ bWYAoPZPopoX4YyhjrkCe/u74YsjZUQM =SavU -----END PGP SIGNATURE-----

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[ANN] Boost 1.39.0
by Beman Dawes 02 May '09

02 May '09

Boost 1.39.0 is available for download from SourceForge. See http://sourceforge.net/project/showfiles.php?group_id=7586&package_id=8041&… New Libraries: Signals2. Updated Libraries: Asio, Flyweight, Foreach, Hash, Interprocess, Intrusive, Program.Options, Proto, PtrContainer, Range, Unordered, Xpressive. Updated Tools: Boostbook, Quickbook. Plus the usual bug fixes to numerous libraries. Please report any problems to the Boost users or developers mailing list. Thanks, --Beman Dawes, Daniel James, and all the other Boosters who help get releases out

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Recent compilation troubles with gcc atomics
by tom fogal 02 May '09

02 May '09

Hello all, Recently I have noted more than one posting to this list with regards to compilation troubles on some platforms utilizing Gnu C++ or Intel's C++ compiler. Specifically, I am referring to linking errors with some of gcc's internal `atomics' functions, e.g. `__sync_fetch_and_add'. Some searching brings up: http://www.mail-archive.com/debian-bugs-closed@lists.debian.org/msg197119.h… http://www.nabble.com/Building-for-ARM926EJ-S-td16447579.html http://groups.google.com/group/boost-list/browse_thread/thread/8e757cc2788d… https://svn.boost.org/trac/boost/ticket/2525 http://www.nabble.com/issues-with-unit-tests-on-intel-32-bit,-gcc-4.3,-unde… I also happen to follow the libstdc++ mailing list, which has just seen an elucidating post by Joseph S. Myers: http://gcc.gnu.org/ml/gcc/2009-05/msg00039.html In it, he notes that the availability of these builtins is not solely a function of the compiler version. In particular, the platform (CPU, OS, runtime support) seems to be a factor, as well as the backend code generation options (i.e. -march gcc compiler option). He also suggests that the only reliable methodology for discovering the availability of these functions/builtins is by doing link-time tests. I mention as much because (unverified) I think boost's current solution is #ifdefs based on architecture and compiler version, which I think is fighting a losing battle. I hope this information is useful for those stuck on the problem, and/or boost developers. Cheers, -tom

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[asio] async write handler is not called until the socket is not closed
by Roman Shmelev 02 May '09

02 May '09

Hi! I've got very strange problem - handler passed to async_write is not called in time. What I mean - it is called only when socket is closed - then handler is invoked many times. Sometimes it is so, sometimes everything is fine. The main thing is that traffic exists. I mean - async writes get completed. I call io_service.run() in proper time, etc. Another moment - the first two times the handler is invoked, but not more. As I guess, the problem is somewhere in my code. But I ask you to point to probable reasons of such behaviour that breaks asio rules..

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[iterator] std::sort on zip_iterator
by Jeremiah Willcock 02 May '09

02 May '09

I would like to sort two separate vectors of numbers, treating corresponding elements of the two vectors as tuples and sorting the tuples. In particular, I am only comparing the first elements of the tuples; that may or may not be relevant to my problem. An example program is: #include <vector> #include <algorithm> #include <iostream> #include <boost/tuple/tuple.hpp> #include <boost/iterator/zip_iterator.hpp> struct compare_first_elements_in_tuples { template <typename Tuple> bool operator()(const Tuple& a, const Tuple& b) const { return (a.template get<0>()) < (b.template get<0>()); } }; int main(int, char**) { size_t a_data[5] = {0, 2, 1, 2, 4}; size_t b_data[5] = {1, 1, 5, 3, 7}; std::vector<size_t> a(a_data, a_data + 5); std::vector<size_t> b(b_data, b_data + 5); std::cout << "Before:"; for (size_t i = 0; i < a.size(); ++i) { std::cout << " (" << a[i] << ", " << b[i] << ")"; } std::cout << std::endl; typedef std::vector<size_t>::iterator vec_iter; typedef boost::zip_iterator<boost::tuple<vec_iter, vec_iter> > zip_iter; std::sort(zip_iter(boost::make_tuple(a.begin(), b.begin())), zip_iter(boost::make_tuple(a.end(), b.end())), compare_first_elements_in_tuples()); std::cout << "After:"; for (size_t i = 0; i < a.size(); ++i) { std::cout << " (" << a[i] << ", " << b[i] << ")"; } std::cout << std::endl; return 0; } On gcc 4.0.1, the sort operation results in the element (2, 1) (a pair of corresponding elements in a and b) being duplicated, while the element (1, 5) does not appear in the result at all: Before: (0, 1) (2, 1) (1, 5) (2, 3) (4, 7) After: (0, 1) (2, 1) (2, 1) (2, 3) (4, 7) I suspect the problem is related to the fact that zip_iterator does not return a "real" reference when dereferenced. Am I mistaken about this? Is the code above supposed to work? If not, is there an alternative way to sort one sequence while swapping elements in another in a corresponding way? I am not able to join the two input sequences into a single sequence of pairs because of other factors in the use case for this code. Thank you for your help. -- Jeremiah Willcock

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General C++: Class Method Signatures Miss-Match
by Etienne Philip Pretorius 02 May '09

02 May '09

Hello list, I know this is not boost related, but I will appreciate it if anyone could shed some light on what is happening here? Compiler error: xml.cpp: In member function ‘xml::document& xml::document::parse(std::vector<unsigned char, std::allocator<unsigned char> >&)’: xml.cpp:25: error: no matching function for call to ‘xml::document::characters(std::basic_string<unsigned int, std::char_traits<unsigned int>, std::allocator<unsigned int> >)’ xml.hpp:24: note: candidates are: virtual void xml::document::characters(unicode::string) unicode::string definition starts: namespace unicode { typedef std::size_t code_point; class string : public std::basic_string<code_point> { Is "std::basic_string<unsigned int, std::char_traits<unsigned int>, std::allocator<unsigned int> >" not the same as "unicode::string"? If not why is it not? Etienne

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[BGL] unordered_set<std::vector<edge_descriptor> >
by Johan Oudinet 02 May '09

02 May '09

Hi, I want to keep a set of paths, which are implemented as a vector of edge_descriptor. I don't care about the order. I just have to add paths and be able to know the number of different paths present in the set. So, I plan to use unordered_set but I'd like to know you opinion about a hash function, since AFAIK, unordered_set is like an hash_set? My main issue is to use as few memory as possible, because there will have a lot of paths in the set. Any idea? Thanks for your help. -- Johan

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