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circular_buffer_space_optimized possible bug
by Birju Prajapati 24 Feb '09

24 Feb '09

Hi, When I run the following code: int main() { boost::circular_buffer_space_optimized<int> buf; std::cout << buf.size() << std::endl; buf.push_back(1); std::cout << buf.size() << std::endl; } I get the output 0 0 Is this a bug? This is boost 1.38, gcc 4.3.2 It works fine with boost 1.35, gcc 4.1.2 (gives the output 0,1) TIA Birju Schneider Trading 4th Floor, 25 Copthall Avenue London EC2R 7BP -------------------------------------------------------- Message from: Birju.Prajapati(a)schneidertrading.com Message to: boost-users(a)lists.boost.org Attached files: 0 This e-mail and any files transmitted with it are confidential, may be legally privileged, and are for the sole use of the intended recipient. Copyright in this e-mail and any accompanying document created by us is owned by us. If you are not the intended recipient of this e-mail or any part of it please telephone our IT Department at the number shown above or by e-mail at info(a)schneidertrading.com. You should not use or disclose to any other person the contents of this e-mail or its attachments (if any), nor take copies. This e-mail is not a representation or warranty and is not intended nor should it be taken to create any legal relations, contractual or otherwise. Schneider Trading Associates Ltd (Registration No. 3692131) is incorporated in England and Wales and the registered office is at 25 Copthall Avenue, London EC2R 7BP. The company is authorised and regulated by the Financial Services Authority

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How to access each elements of a thread group separately
by Johan Mazel 24 Feb '09

24 Feb '09

Hi I'm using several threads to do some parallel work. But I need to stop them separatly through the interrupt method. In order to store all these threads, I thought that I would use the thread_group class since I cannot use the vector class. But it looks like I cannot acces an element of a thread group (to interrupt it separately for example). Is there anyway of doing this that I'm not aware of ? Thanks in adavnace for the help. Johan Mazel

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boost::serialization - track_never, load and save in cpp file?
by Martin Trappel 24 Feb '09

24 Feb '09

Hi. To support the serialization of a class I don't want to change anything, I have added free save and load function. (See the test code below.) It compiles and appears to work. I have the following questions: * Is it OK to put the save & load definitions in a separate implementation file? * Is it OK to specify track_never in a cpp file? Will this cause problems if someone else tries to serialize a map<int, string> ? thanks! - Martin - global_serialization.h - // ... class MyComplexClass; // ... namespace boost { namespace serialization { // Declare save and load for MyComplexClass template<class Archive> void save(Archive & ar, const MyComplexClass& t, unsigned int version); template<class Archive> void load(Archive & ar, MyComplexClass& t, unsigned int version); } } // Split: BOOST_SERIALIZATION_SPLIT_FREE(MyComplexClass); ***** - complex_class_serialization.cpp - // ... #include "ComplexClass.h" // ... typedef std::map<int, std::string ser_map_t; BOOST_CLASS_TRACKING(ser_map_t, boost::serialization::track_never); namespace boost { namespace serialization { template<class Archive> void save(Archive & ar, const MyComplexClass& t, unsigned int version) { // the relevant information to be serialized for // instances of MyComplexClass can be represented // by a map<int, string> ser_map_t m; // ... fill m object from t object ar << m; // Serialize } template<class Archive> void load(Archive & ar, CBoxHandler & t, unsigned int version) { ser_map_t m; ar >> m; // ... init t object from m } } // namespace serialization } // namespace boost

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[mpl & type_traits]
by Robert Jones 24 Feb '09

24 Feb '09

Simple questions from a metaprogramming newbie... Why do we have mpl::true_ and true_type? Are they interchangable? Is is_same the same as mpl::equal? Thanks, Rob.

2 1

Problem with regular expression's validity and matching
by Paulino De Assis Fong 24 Feb '09

24 Feb '09

Hi, I have two problems that I would need some help. Thanks in advance. Question 1: Please consider the regular expression to match US phone number below: (($\d{3}$?)|(\d{3}))([\s-./]?)(\d{3})([\s-./]?)(\d{4}) boost doesn't like it and it will throw an exception for the code below while it seems to be fine in online regex tester and .Net Regex library. I don't know what is imcompatiable with boost regex library. Please advice. try { boost::wregex expr(csRegex, boost::regex::normal | boost::regbase::icase); } catch (boost::exception const& e) { } Question 2: Please consider the regular expression to match US SSN below: (?!000)([0-6]\d{2}|7([0-6]\d|7[012])) ([ -])? (?!00)\d\d([ -|])? (?!0000)\d{4} It didn't throw an exception for this regular expression but it wasn't able to match any SSN at all in any format while it matches fine using other regular expression engine. Am I missing something? if (expr.expression()) { // Boost Regex usage flags boost::regex_constants::match_flag_type flags = boost::regex_constants::match_normal; // Start the boost regular expression iterator boost::wcregex_iterator start(boost::make_regex_iterator (StringToMatch, expr, flags)), end; while (start != end) { boost::match_results<const wchar_t*> match = *start; . . . } }

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Boost's automatic selection of debug vs release libaries on link - how to disable?
by Damien Hocking 24 Feb '09

24 Feb '09

Hello everyone, I've noticed that when linking Boost libraries, the linker implicitly knows whether it requires a debug or a release Boost library, and what the full name of the library is. E.g. on Windows the linker wants "boost_serialization-vc80-mt-d-1_37.lib" in debug and "boost_serialization-vc80-mt-1_37.lib" in release. I'm working in an SCons build system where SCons runs the show and the Boost libraries will be custom-renamed and the linker told specifically what libraries to link. Is there any way to disable this implicit naming feature in the bjam build step through a compiler option? Damien

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Release notes for Boost.Test
by Ross Boylan 24 Feb '09

24 Feb '09

http://www.boost.org/doc/libs/1_38_0/libs/test/doc/html/intro.html says --------------------------------- Release notes For more details see complete release notes. --------------------------------- There are no hyperlinks in that text. What is this referring to? It does not seem to be the global release notes, which don't mention changes in test even when they occurred (e.g., 1.33). Nor can I find something in the docs for test, or groping around in the svn source tree. Ideally, I'd like a history of changes across different releases, so I know what I need to make my code compatible with the different versions. I'm hoping for something a little higher level than svn diff. Thanks. Ross Boylan

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[boost::system] Is the library abstraction general enough?
by Lian Cheng 24 Feb '09

24 Feb '09

Hi, all I'm currently building an asynchronous MySQL client API based on Boost.Asio, whose error handling is based on Boost.System. And thus, I wrote some code to wrap MySQL error codes and error messages with Boost.System. While writing the code, I found that the library doesn't provide a general enough abstraction. As the document says, there should always be only one instance of each error_category class. And each error_code instance communicates with its error_category through only the error number. Then here is the problem. MySQL error code is a property of a single MySQL connection. The mysql_errno() and mysql_error() functions both require a MYSQL* connection handle as parameter to retrieve the last error number and error message of the given MySQL connection. And the error messages provided by MySQL API are actually printf format strings. The mysql_error() function fills the format strings with information related to the MYSQL* handle. But in Boost.System, I've got no idea how to pass the connection handle to the error_category::message() function so that a proper error message can be retrieved. Is there any way to fix this problem? Or the library itself is just not general enough? You see, not all error numbers can be directly mapped to a well defined error message string. Cheers Cheng

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[signals2] VS 2005 error with deconstruct.hpp
by Nat Goodspeed 24 Feb '09

24 Feb '09

One small glitch in the 2009-02-11 signals2 snapshot [1]. When a source file containing only: #include <boost/signals2.hpp> is compiled with Visual Studio 2005, it produces: cl /EHsc /I libraries/include signals2-glitch.cpp Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 14.00.50727.762 for 80x86 Copyright (C) Microsoft Corporation. All rights reserved. signals2-glitch.cpp libraries/include\boost/signals2/deconstruct.hpp(510) : error C2874: using-declaration causes a multiple declaration of 'boost::signals2::detail::deconstruct_access' libraries/include\boost/signals2/deconstruct.hpp(233) : see declaration of 'boost::signals2::detail::deconstruct_access' This is the line in question, near the bottom of boost/signals2/deconstruct.hpp: using detail::deconstruct_access; I'm not sure what the intent is for that line, but removing it solves that problem without, as far as I'm aware, introducing new problems. I've attached a patch file. This line caused me no problems on Mac or Linux. Neither does its removal. [1] http://www.boostpro.com/vault/index.php?action=downloadfile&filename=signal… *** boost/signals2/deconstruct.hpp~ Thu Feb 5 18:58:10 2009 --- boost/signals2/deconstruct.hpp Mon Feb 23 15:05:44 2009 *************** *** 507,514 **** return detail::deconstruct_access::deconstruct<T>(a1,a2,a3,a4,a5,a6,a7,a8,a9); } - using detail::deconstruct_access; - #endif } // namespace signals2 --- 507,512 ----

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Re: [Boost-users] boost::exception - leaking error_info
by Bruce Laing 24 Feb '09

24 Feb '09

> Re: [Boost-users] boost::exception - leaking error_info > Date: Mon, 23 Feb 2009 11:01:08 -0800 > From: Emil Dotchevski <emildotchevski(a)gmail.com> > Subject: Re: [Boost-users] boost::exception - leaking error_info > On Mon, Feb 23, 2009 at 9:31 AM, Bruce Laing > <bruce.laing(a)eng-software.com> wrote: > > Emil, > > > > The platform is vc++ 8, boost 1.37. > > > > Please do keep us posted, it's kind of important for exception objects > not to leak memory. :) Emil, Quick update: my problem seems to have been due to conflicting instances of the runtime library coming into the link. I haven't determined which component is bringing in the dynamic CRT, but in any case, changing /MTd to /MDd fixes the leak, indicating a problem in my project setup and compiler/linker switches, rather than a problem with either boost::exception or the way my code was using the library. - Bruce

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[ASIO] io_service.run() call is not blocking until async_write completes
by nick aschberger 23 Feb '09

23 Feb '09

Hi Folks, I am using boost 1.36, and I have a C++ class that wraps calls to boost::asio sockets. There are two important functions: WriteData -- takes a vector of uint8_t's and uses async_write. WaitForPreviousWritestoComplete -- Here the user expects to block until all their previous writes are complete. Effectively this just calls io_service.run(). A user of this class can will WriteData a few times, and then do some other processing for a bit while the async_write is happening in the background, and then they should block at io_service.run() until the writes complete (and error status etc is checked). It was my understanding that io_service.run() call would block the thread of execution at that point until the pending writes on my output socket were complete. Am I wrong in my interpretation, because I see the user effectively doing: async_write async_write async_write io_service.run() async_write async_write io_service.run() The first call to io_service.run() correctly calls my message handler 3 times, for the 3 writes. The second call to io_service.run() I expect to see the handler called twice, but it is not called at all! If I get a bit tricky and do something like: async_write async_write async_write while (!all_writes_comple_flag){ io_service.run() } (the handler will set all_writes_comple_flag when all writes are complete :) ) then the code is effectively busy waiting at that point until it is done, but I do see the handler entered when I expect. Is there some timing issue occurring here? Perhaps the thread that is managing the socket stuff not had a chance to register that it has a pending write waiting? Am I misinterpreting what boost means in the documentation by saying the io_service.run() function blocks? If I am, what should I do to wait until all asynchronous writes are complete? thanks Nick

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Boost.multi_index: how to use a member function instead ofoperator<()?
by Joost Kraaijeveld 23 Feb '09

23 Feb '09

Hi, I want to use in index based on a member function that returns a bool if an element is smaller than an other element like operator<. But I cannot find how to do that. e.g. using namespace ::boost; using namespace ::boost::multi_index; class Object{ bool operator<(const Object& rhs) const; bool fn(const Object& rhs) const; } struct FnIndex{}; typedef multi_index_container< Object, indexed_by < ordered_unique< identity< Square > >, // this uses operator<(const Object&) I believe? ordered_unique< tag< FnIndex >, ?????????????? > > > ObjectContainer; If this possible, what should I use in the place of ????????? TIA -- Groeten, Joost Kraaijeveld Askesis B.V. Molukkenstraat 14 6524NB Nijmegen tel: 024-3888063 / 06-51855277 fax: 024-3608416 web: www.askesis.nl

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proto user guide e.g.
by Hicham Mouline 23 Feb '09

23 Feb '09

Hi, continuing to work through the user guide boost_1_38_0/doc/html/proto/users_guide.html, I reached the section Retaining POD-ness with BOOST_PROTO_EXTENDS() I fail to compile the following code with intel10: --------------------------CODE----------------------------- #include <iostream> #include <vector> #include <cmath> #include <boost/proto/core.hpp> #include <boost/proto/tags.hpp> #include <boost/proto/context.hpp> #include <boost/proto/domain.hpp> #include <boost/mpl/assert.hpp> using namespace boost; // Define a placeholder type template<int I> struct placeholder {}; // A type to be used as a domain tag (to be defined below) struct calculator_domain; struct calculator_context : proto::callable_context< calculator_context const > { // Values to replace the placeholders std::vector<double> args; // Define the result type of the calculator. // (This makes the calculator_context "callable".) typedef double result_type; // Handle the placeholders: template<int I> double operator()(proto::tag::terminal, placeholder<I>) const { return this->args[I]; } }; // The calculator<> expression wrapper makes expressions // function objects. template< typename Expr> struct calculator { // Use BOOST_PROTO_BASIC_EXTENDS() instead of proto::extends<> to // make this type a Proto expression extension: BOOST_PROTO_BASIC_EXTENDS(Expr, calculator<Expr>, calculator_domain) // Define operator[] to build expression templates: BOOST_PROTO_EXTENDS_SUBSCRIPT() // Define operator= to build expression templates: BOOST_PROTO_EXTENDS_ASSIGN() typedef double result_type; // Hide base_type::operator() by defining our own which // evaluates the calculator expression with a calculator context. result_type operator()( double d1 = 0.0, double d2 = 0.0 ) const { // As defined in the Hello Calculator section. calculator_context ctx; // ctx.args is a vector<double> that holds the values // with which we replace the placeholders (e.g., _1 and _2) // in the expression. ctx.args.push_back( d1 ); // _1 gets the value of d1 ctx.args.push_back( d2 ); // _2 gets the value of d2 return proto::eval(*this, ctx ); // evaluate the expression } }; // Define a calculator domain. Expression within // the calculator domain will be wrapped in the // calculator<> expression wrapper. struct calculator_domain : proto::domain< proto::generator<calculator> > {}; int main() { calculator< proto::terminal< placeholder<0> >::type > const _1 = {{{}}}; calculator< proto::terminal< placeholder<1> >::type > const _2 = {{{}}}; std::cout << ((_1 + _2)(45., 56.)) << std::endl; } -------------------------------- END CODE -------------------------------- The error is: 1>using typeof emulation 1>C:\Program Files (x86)\boost_1_38_0\boost/proto/generate.hpp(153): error: no suitable user-defined conversion from "const boost::proto::exprns_::expr<boost::proto::tag::plus, boost::proto::argsns_::list2<const calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<0>>, 0L>> &, const calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<1>>, 0L>> &>, 2L>" to 1> "calculator<boost::proto::exprns_::expr<boost::proto::tag::plus, boost::proto::argsns_::list2<const calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<0>>, 0L>> &, const calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<1>>, 0L>> &>, 2L>>" exists 1> return Extends<Expr>(expr); 1> ^ 1> detected during: 1> instantiation of "Extends<Expr> boost::proto::generatorns_::generator<Extends>::operator()(const Expr &) const [with Extends=calculator, Expr=boost::proto::exprns_::expr<boost::proto::tag::plus, boost::proto::argsns_::list2<const calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<0>>, 0L>> &, const calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<1>>, 0L>> &>, 2L>]" at 1> line 145 of "C:\Program Files (x86)\boost_1_38_0\boost/proto/operators.hpp" 1> instantiation of "Left::proto_domain::result<void (boost::proto::exprns_::expr<Tag, boost::proto::argsns_::list2<Left &, Right &>, boost::proto::argsns_::list2<Left &, Right &>::arity>)>::type boost::proto::detail::as_expr_if<Tag, Left, Right, Left::proto_is_expr_, Right::proto_is_expr_>::make(Left &, Right &) [with Tag=boost::proto::tag::plus, Left=const calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<0>>, 0L>>, 1> Right=const calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<1>>, 0L>>]" at line 290 of "C:\Program Files (x86)\boost_1_38_0\boost/proto/operators.hpp" 1> instantiation of "const boost::proto::detail::as_expr_if<boost::proto::tag::plus, const Left, const Right, void, void>::type boost::proto::exprns_::operator+(const Left &, const Right &) [with Left=calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<0>>, 0L>>, Right=calculator<boost::proto::exprns_::expr<boost::proto::tag::terminal, boost::proto::argsns_::term<placeholder<1>>, 0L>>]" at line 120 of ".\Test4.cpp" 1> 1>compilation aborted for .\Test4.cpp (code 2)

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Re: [Boost-users] proto user guide e.g.
by Hicham Mouline 23 Feb '09

23 Feb '09

I was using the wrong generator for the domain, it was explained later in the user guide. Apologies,

1 0

[Serialization] Error in serialization of a hash map
by Jack Mullen 23 Feb '09

23 Feb '09

Hi, I'm having a bit of trouble while using the serialization library. (Boost v1.35, gcc, Red Hat Linux). I have a class containing a hash_map (key=string, value=shared_ptr to a class containing a deque): HashMapClass{ friend class boost::serialization::access; template <class Archive> void serialize(Archive &ar, const unsigned in t version){ ar & map; } __gun_cxx::hash_map<std::string const, boost::shared_ptr<DequeClass> map; } //create instance HashMapClass hashMap; // fill hashmap ... //perform serialization every hour or something std::ofstream ofs("file.txt"); boost::archive::binary_oarchive oa(ofs); const HashMapClass &map = hashMap; oa << map; The Problem: This works fine for several saves. I can see the file created changing each time the serialization is done. Then after about four or five saves, it seg faults at the place described below. It looks to me like it's having problems iterating over the hash_map. Any advice on how to diagnose or fix this would be appreciated, Many thanks Jack Segfault at: (__gnu_cxx::_Hashtable_const_iterator<std::pair<std::string const, boost::shared_ptr<HashMapClass> >, std::string const, __gnu_cxx::hash<std::string const>, std::_Select1st<std::pair<std string const, boost::shared_ptr<HashMapClass> > >, std::equal_to<std::string const>, std::allocator<boost::shared_ptr<HashMapClass> > >::operator++()+0xe)[0x65a825a] (boost::archive::detail::oserializer<boost::archive::binary_oarchive, __gnu_cxx::hash_map<std::string const, boost::shared_ptr<HashMapClass>, __gnu_cxx::hash<std::string const>, std::equal_to<std::string const>, std::allocator<boost::shared_ptr<HashMapClass> > >::save_object_data(boost::archive::detail::basic_oarchive&, void const*) const+0x1b2)[0x65a90da] (/usr/lib/libboost_serialization-gcc34-mt-1_35.so.1.35.0(boost::archive::detail::basic_oarchive_impl::save_object(boost::archive::detail::basic_oarchive&, void const*, boost::archive::detail::basic_oserializer const&)+0xd1)[0x8497cd] (/usr/lib/libboost_serialization-gcc34-mt-1_35.so.1.35.0(boost::archive::detail::basic_oarchive::save_object(void const*, boost::archive::detail::basic_oserializer const&)+0x23)[0x849213] (boost::archive::detail::oserializer<boost::archive::binary_oarchive, HashMapClass>::save_object_data(boost::archive::detail::basic_oarchive&, void const*) const+0x15c)[0x65a7db4] (/usr/lib/libboost_serialization-gcc34-mt-1_35.so.1.35.0(boost::archive::detail::basic_oarchive_impl::save_object(boost::archive::detail::basic_oarchive&, void const*, boost::archive::detail::basic_oserializer const&)+0xd1)[0x8497cd] (/usr/lib/libboost_serialization-gcc34-mt-1_35.so.1.35.0(boost::archive::detail::basic_oarchive::save_object(void const*, boost::archive::detail::basic_oserializer const&)+0x23)[0x849213]

2 1

Re: [Boost-users] boost::exception - leaking error_info
by Bruce Laing 23 Feb '09

23 Feb '09

> > > Date: Fri, 20 Feb 2009 19:17:55 -0800 > From: Emil Dotchevski <emildotchevski(a)gmail.com> > Subject: Re: [Boost-users] boost::exception - leaking error_info > On Fri, Feb 20, 2009 at 3:00 PM, Bruce Laing > <bruce.laing(a)eng-software.com> wrote: > > This program seems to be leaking boost::exception::error_info objects. > > Is there something missing here? > > > > - Bruce > > > > What platform? Do you have a complete program that shows the problem? > > This test seems to work as expected: > > #include "boost/exception.hpp" > > class > counter > .... > int > main() > { > c=0; > try > { > throw_func(); > } > catch( an_exception & ) > { > assert(c>0); > } > assert(!c); > } > > Emil Dotchevski > Reverge Studios, Inc. > http://www.revergestudios.com/reblog/index.php?n=ReCode > Emil, The platform is vc++ 8, boost 1.37. Since submitting my inquiry to the list, I cut my boost.exception code out into a separate test program that is very similar to the test code you gave in your reply (thanks for that) , but my test program does not leak, so the problem seems to involve some aspect of context from the original surrounding code that I'm not yet able to identify. I'll write back with an update if I can isolate the interaction that triggers the leakage. - Bruce

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How to use noncopyable?
by Yang Zhang 23 Feb '09

23 Feb '09

Hi, I can't figure out how to properly use noncopyable. I'm always getting things like "has a non-virtual destructor" warnings. In fact, compiling noncopyable_test.cpp gives me: $ g++ -Wall -g3 -o noncopyable_test noncopyable_test.cpp -Wextra -Wconversion -Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings -Winit-self -Wno-unused-parameter -Wparentheses -Wmissing-format-attribute -Wfloat-equal -Winline -Woverloaded-virtual -Wsign-promo -Wc++0x-compat -Wsynth /opt/armed/include/boost/noncopyable.hpp: In copy constructor ‘<unnamed>::DontTreadOnMe::DontTreadOnMe(const<unnamed>::DontTreadOnMe&)’: /opt/armed/include/boost/noncopyable.hpp:27: error: ‘boost::noncopyable_::noncopyable::noncopyable(const boost::noncopyable_::noncopyable&)’ is private noncopyable_test.cpp:22: error: within this context noncopyable_test.cpp: In function ‘int main()’: noncopyable_test.cpp:32: note: synthesized method ‘<unnamed>::DontTreadOnMe::DontTreadOnMe(const<unnamed>::DontTreadOnMe&)’ first required here /opt/armed/include/boost/noncopyable.hpp: In member function ‘<unnamed>::DontTreadOnMe&<unnamed>::DontTreadOnMe::operator=(const<unnamed>::DontTreadOnMe&)’: /opt/armed/include/boost/noncopyable.hpp:28: error: ‘const boost::noncopyable_::noncopyable& boost::noncopyable_::noncopyable::operator=(const boost::noncopyable_::noncopyable&)’ is private noncopyable_test.cpp:22: error: within this context noncopyable_test.cpp: In function ‘int main()’: noncopyable_test.cpp:33: note: synthesized method ‘<unnamed>::DontTreadOnMe&<unnamed>::DontTreadOnMe::operator=(const<unnamed>::DontTreadOnMe&)’ first required here Any hints? Thanks in advance. -- Yang Zhang http://www.mit.edu/~y_z/

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[Range] Single Pass Range functionality
by Edward Diener 23 Feb '09

23 Feb '09

In the Boost Range documentation describing the Range concepts for a single pass range it lists in the expression semantics post-condition for boost::begin(a): "boost::begin(a) is either dereferenceable or past-the-end. It is past-the-end if and only if boost::distance(a) == 0." However the documentation for single pass range does not list boost::distance as a valid expression nor in the reference section is boost::distance listed as a single pass range function. Is boost::distance a valid function when applied to a single pass range ?

2 2

asio: take back ownership of native descriptor
by Koen Deforche 23 Feb '09

23 Feb '09

Dear all, We have been enjoying using asio alot to build cross-platform networking applications. Just recently, however, we have encountered a limitation that seems impossible to work around, and, would only require a small addition in the API to accomodate. We are trying to add one or more native socket descriptors into asio's reactor to be informed when it is possible to write or read from these descriptors. Therefore, we are creating a tcp::socket and assign() to it a native descriptor. This works, but it seems that nothing can prevent asio from closing the connection in ~tcp::socket() (which does not seem logic since asio did not open the connection in the first place). Should there not be a method to 'take' (back) the descriptor from the asio socket, which resets the socket to the same state as its default constructor ? We tried the workaround that was suggested on the mailinglist, which is to dup() the descriptor. This works on Linux. Unfortunately, dup() is not available on Windows platforms, and when trying to workaround this by using Windows' native methods, we hit the same (so far, unsolved?) problem of this post: http://thread.gmane.org/gmane.comp.lib.boost.user/44269 Regards, koen

1 0

How to implementing a conditional wait
by Daniele Barzotti 23 Feb '09

23 Feb '09

Hi, I have to do a simple task, but I'm quite confused. I have a class that sends some data on RS232 and wait for a answer. (What in Windows is WaitForSingleObject) void ATDispatcher::OnDataReveived() { // Data received from RS232 serial_port.GetData(&buffer); boost::lock_guard<boost::mutex> lock(mut); data_ready = true; cond.notify_one(); }; void ATDispatcher::AtDispatcher(SerialPort& device) : _device(device) { // Connecting the slot for receiving event _device.OnData(boost::bind(&ATDispatcher::OnDataReceived(), &this)); }; int ATDispatcher::SendCommand(std::string cmd, bool waitOK = true, bool decode_answer = true int cmd_timeout = COMMAND_TIMEOUT) { boost::unique_lock<boost::mutex> lock(mut); boost::xtime xt; xtime_get(&xt,boost::TIME_UTC); xt.sec += cmd_timeout; data_ready = false; //Send data.... while(!data_ready) { cond.timed_wait(lock, xt); } }; Ok, The OnDataReceived is called from the SerialPort thread when the data is available. In the SendCommand I have to wait for a timeout or until the answer is arrived...how can I do it? Thanks! Daniele.

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[1.38.0] PDF package of Boost documentation released.
by John Maddock 22 Feb '09

22 Feb '09

Folks, A package containing PDF versions of Boost's documentation is now available for Boost-1.38.0 from the usual sourceforge download site: http://sourceforge.net/project/showfiles.php?group_id=7586&package_id=15971… Please note that due to the diverse range of tools in use within Boost it has not been possible to produce PDF's for all of Boost's libraries, those currently included as PDF's are: accumulators any array asio bimap range complex-tr1 concepts config conversion date_time foreach function hash interprocess intrusive iterator math-gcd math mpi octonion optional phoenix program_options proto python_tutorial quaternion ref regex scope_exit signals static_assert string_algo thread tr1 tribool type_traits typeof units unordered variant xpressive Documentation for the following tools are also included in this package: bjam boost_build boostbook quickbook Regards, John Maddock.

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boost::iostreams : equivalent of std::getline() in boost
by vandamme 22 Feb '09

22 Feb '09

Hello ! I want to use boost to read a text file like this : boost::iostreams::file_source file(filename.c_str()); But, when I want to get each single line with getline(), it doesn't compile : while (std::getline(file, line)) { ...} // COMPILATION ERROR What's the equivalent in boost for std::getline() ? Thks. -- View this message in context: http://www.nabble.com/boost%3A%3Aiostreams-%3A-equivalent-of-std%3A%3Agetli… Sent from the Boost - Users mailing list archive at Nabble.com.

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Boost.Test: How to create a multi-module (multi-file) test suite or how to link multiple auto test cases into one executable?
by Leonid Shlyapnikov 22 Feb '09

22 Feb '09

Hi everybody! I got a bit rusty with C++. Can someone help me to understand how I can create a Boost.Test suite that contains test cases from multiple modules (multiple cpp files)? Lets say I have: file: ATest.cppp: ----------------------------------------------------------------------- #define BOOST_TEST_MODULE ATest #include <boost/test/included/unit_test.hpp> BOOST_AUTO_TEST_CASE(testA1) { .... } BOOST_AUTO_TEST_CASE(testA2) { .... } ----------------------------------------------------------------------- file: BTest.cppp: ----------------------------------------------------------------------- #define BOOST_TEST_MODULE BTest #include <boost/test/included/unit_test.hpp> BOOST_AUTO_TEST_CASE(testB1) { .... } BOOST_AUTO_TEST_CASE(testB2) { .... } ----------------------------------------------------------------------- Compilation passes all right. Linker gives: In function `boost::unit_test::output::compiler_log_formatter::log_finish(std::basic_ostream<char, std::char_traits<char> >&)': /usr/include/c++/4.2/bits/char_traits.h:291: multiple definition of `boost::unit_test::output::compiler_log_formatter::log_finish(std::basic_ostream<char, std::char_traits<char> >&)' I understand this error (even after 3-4 years of only Java :). So, question: Is there any way to link multiple auto test cases into one executable file? I have not found any information on this. Does it mean that if I want to have one executable that runs all my test cases I need to put/include all test case definitions into one cpp file? Thanks a lot, Leonid Shlyapnikov

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bjam cross compilation using mingw32 doesn't use mingw32-ar ?
by Ákos Maróy 22 Feb '09

22 Feb '09

I'm trying to cross-compile boost using mingw32, doing the following steps: echo "using gcc : : mingw32-g++ ;" >> user-config.jam bjam target-os=windows threading=multi threadapi=win32 link=static runtime-link=static --prefix=../../usr-mingw --includedir=../../usr-mingw/include --libdir=../../usr-mingw/lib install this goes down fine. but when I'm trying to link to one of the boost libraries, I get the following: mingw32-g++ -m32 -g -L../../usr-mingw/lib -o tests test_plane_position.o test_position_recorder.o test_position_player.o plane_position.o position_recorder.o position_player.o tests.o -llibboost_test_exec_monitor-mgw41-mt-s-1_38 -llibboost_unit_test_framework-mgw41-mt-s-1_38 ../../usr-mingw/lib/libboost_test_exec_monitor-mgw41-mt-s-1_38.lib: could not read symbols: Archive has no index; run ranlib to add one collect2: ld returned 1 exit status make: *** [tests] Error 1 where: $ file ../../usr-mingw/lib/libboost_unit_test_framework-mgw41-mt-s-1_38.lib ../../usr-mingw/lib/libboost_unit_test_framework-mgw41-mt-s-1_38.lib: current ar archive I did some search, and one suggestion was that the build process didn't use mingw32-ar for creating the libraries? if so, how could I make bjam use mingw32-ar instead of just ar? or is something else the issue? Akos (of course I could just run ranlib on these libs, but my expectation was that the boost build / install process would produce libraries that one could link to right away)

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[signals2][review] The review of the signals2 library (formerly thread_safe_signals) begins today, Nov 1st
by Stjepan Rajko 22 Feb '09

22 Feb '09

Hello all, The review for the Signals2 library (formerly known as thread_safe_signals) submitted by Frank Mori Hess begins today (Nov 1st) and is scheduled to end on Nov 10th. I would like to thank Franz Alt, Terry Golubiewski, Doug Gregor, Ravikiran Rajagopal and Andrew Webber for making this review possible by committing to reviewing the library. How to submit a review: -------- As usual, EVERYONE is welcome to participate in the review discussions and to submit a review. I strongly encourage participation from reviewers that would examine the library from a purely user standpoint (commenting on the interface and / or the documentation), as well as reviewers that would be willing to look into the details of the implementation (i.e., you don't have to focus on both). Here are some questions you might want to answer in your review (feel free to skip those that don't apply to your analysis): * What is your evaluation of the design? * What is your evaluation of the implementation? * What is your evaluation of the documentation? * What is your evaluation of the potential usefulness of the library? * Did you try to use the library? With what compiler? Did you have any problems? * How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? * Are you knowledgeable about the problem domain? And finally, every review should answer this question: * Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Please submit your review either to the list or privately to me by the end of the review period. If you send me a review privately I will forward it to the list so the review can be discussed. If you would prefer me to forward your review anonymously (with your name removed) please indicate that in your e-mail. If you are a first time reviewer, here is some more information to get you started: * http://www.boost.org/community/reviews.html has more information on the review process * the review officially takes place on both the boost dev and boost-user lists, but typically more of the discussion happens on the boost dev list * if you want to get a feel for past reviews, you can find them in the archives (see http://www.boost.org/community/groups.html) - the past review dates are on the review schedule (http://www.boost.org/community/review_schedule.html) Typically, there is a period of discussion between the reviewers and the author, with official reviews coming in towards the tail end of the review period. About the library: -------- * The library can be downloaded from: http://www.boostpro.com/vault/index.php?&directory=thread_safe_signals (latest version is signals2-2008-10-08.zip) * Documentation is also available online: http://www.comedi.org/projects/signals2/libs/signals2/doc/html/index.html * A synopsis: The Boost.Signals2 library (formerly known as thread_safe_signals) is an implementation of a managed signals and slots system. Signals represent callbacks with multiple targets, and are also called publishers or events in similar systems. Signals are connected to some set of slots, which are callback receivers (also called event targets or subscribers), which are called when the signal is "emitted." Signals and slots are managed, in that signals and slots (or, more properly, objects that occur as part of the slots) can track connections and are capable of automatically disconnecting signal/slot connections when either is destroyed. This enables the user to make signal/slot connections without expending a great effort to manage the lifetimes of those connections with regard to the lifetimes of all objects involved. When signals are connected to multiple slots, there is a question regarding the relationship between the return values of the slots and the return value of the signals. Boost.Signals2 allows the user to specify the manner in which multiple return values are combined. * Relationship to Boost.Signals: This is a thread-safe variant of the original Boost.Signals library. There have been some changes to the interface to support thread-safety, mostly with respect to automatic connection management. The following thread offers some more details on the differences between the two implementations, as well as a plan of a phased replacement of Boost.Signals should Signals2 be accepted: http://tinyurl.com/4sqau3 [nabble] The Signals2 FAQ also covers some differences: http://tinyurl.com/576gl6 Kind regards, Stjepan (review manager)

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