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boost::thread - usage
by Christopher Pisz 03 Aug '11

03 Aug '11

I am trying to make a thread object, so I can later have better control of threads and the resources they are using. So, I started wrapping up a boost::thread. //----------------------------------------------------------------------------- ---------------------------------------------------------------- // BaseThread.h #include <boost/thread/thread.hpp> //----------------------------------------------------------------------------- - /// \brief Thread object that performs a task that is to run once (non- looped) /// \detail Derive from this class and implement the Work method to define the /// work this thread is to perform class BaseThread { public: BaseThread(); /// \brief Deconstructor /// \detail It is required that a derived class make a call to thread_.join() /// in its deconstructor virtual ~BaseThread(); virtual void Start(); virtual int Work() = 0; protected: void Run(); boost::thread thread_; }; //----------------------------------------------------------------------------- ---------------------------------------------------------------- // BaseThread.cpp #include "BaseThread.h" //----------------------------------------------------------------------------- - BaseThread::BaseThread() { } //----------------------------------------------------------------------------- - BaseThread::~BaseThread() { // Wait for the thread to complete thread_.join(); // DEBUG - Does join wait? int x = 1; } //----------------------------------------------------------------------------- - void BaseThread::Start() { boost::thread newThread(boost::bind(&BaseThread::Run, this)); thread_.swap(newThread); } //----------------------------------------------------------------------------- - void BaseThread::Run() { this->Work(); } I am kind of winging it here just going off of the boost documentation and guessing at what I should be doing. This code has a problem in that in order for us to wait for the thread to complete, the derived class is going to have to call thread_.join(). That leaves a bad taste in my mouth as I'd rather the base class take care of all the details, and all the derived class has to worry about is providing a Work method. This class doesn't provide much that boost::thread doesn't already have, but I want to make different classes for additonal requirements. One of which I have in mind is a thread with looped work and a start, stop, method. Making an object out of it will also probably help with derving classes that take care of locking their data...or at least organize it a bit. So the question 1 is, is there a way I can avoid the requirement here that derived classes call thread_.join() and do something different in the base class? Question 2 - What happens to the execution of the thread, when an exception is thrown from the thread that owns boost::thread object or the boost::thread object is destroyed? I'll probably have more questions as I progress.

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Re: [Boost-users] [Containers Library Review] The review of the Containers library by Ion Gaztanaga starts today
by Ion Gaztañaga 03 Aug '11

03 Aug '11

El 03/08/2011 14:41, Mathias Gaunard escribió: > I think it might be good for the people not quite ready to hop onto the > C++0x bandwagon yet. > Plus sometimes it's good to be able to rely on a single portable > reference implementation that actually works with stateful allocators > etc., while it is implementation-defined whether the standard one does. Now that the new standard is nearly finished, the idea is to make them fully compliant, backport to C++03 all possible features and also have a library to experiment new proposals (N1953: Upgrading the Interface of Allocators using API Versioning and N2045: Improving STL allocators), enhancement functions, etc. Best, Ion

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[multi-index][foreach] Iterating over a sequence index (worked in 1.46, broke in 1.47)
by Maxime van Noppen 03 Aug '11

03 Aug '11

Hi, I use BOOST_FOREACH to iterate of a BMI with a sequence index. The code used to work with Boost 1.46 and before, but broke with Boost 1.47. Am I doing something wrong ? ------------------------ #include <iostream> # include <boost/multi_index/hashed_index.hpp> # include <boost/multi_index/member.hpp> # include <boost/multi_index/sequenced_index.hpp> # include <boost/multi_index_container.hpp> # include <boost/foreach.hpp> using namespace ::boost::multi_index; typedef multi_index_container< int, indexed_by< sequenced<> > > bmi_t; typedef bmi_t::nth_index<0>::type seq_idx; const seq_idx& ret(const seq_idx& idx) { return idx; } int main() { bmi_t b; seq_idx& seq = b.get<0>(); // Works BOOST_FOREACH (int i, seq) std::cout << i << std::endl; // Doesn't compile BOOST_FOREACH (int i, ret(seq)) std::cout << i << std::endl; } ------------------------ Note that the offending part is the 'ret(seq)', without it, the code compiles. The error with g++ 4.6.1 is: > In file included from bmi.cc:9:0: > /home/yabo/dev/boost/usr/include/boost/multi_index/sequenced_index.hpp: In destructor ‘boost::foreach_detail_::simple_variant<T>::~simple_variant() [with T = boost::multi_index::detail::sequenced_index<boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, boost::mpl::vector0<mpl_::na> >]’: > /home/yabo/dev/boost/usr/include/boost/foreach.hpp:256:8: instantiated from here > /home/yabo/dev/boost/usr/include/boost/multi_index/sequenced_index.hpp:561:3: error: ‘boost::multi_index::detail::sequenced_index<SuperMeta, TagList>::~sequenced_index() [with SuperMeta = boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, TagList = boost::mpl::vector0<mpl_::na>]’ is protected > /home/yabo/dev/boost/usr/include/boost/foreach.hpp:586:13: error: within this context > /home/yabo/dev/boost/usr/include/boost/multi_index/sequenced_index.hpp: In constructor ‘boost::foreach_detail_::simple_variant<T>::simple_variant(const T&) [with T = boost::multi_index::detail::sequenced_index<boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, boost::mpl::vector0<mpl_::na> >]’: > /home/yabo/dev/boost/usr/include/boost/foreach.hpp:648:95: instantiated from ‘boost::foreach_detail_::auto_any<boost::foreach_detail_::simple_variant<T> > boost::foreach_detail_::contain(const T&, bool*) [with T = boost::multi_index::detail::sequenced_index<boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, boost::mpl::vector0<mpl_::na> >]’ > bmi.cc:28:3: instantiated from here > /home/yabo/dev/boost/usr/include/boost/multi_index/sequenced_index.hpp:549:3: error: ‘boost::multi_index::detail::sequenced_index<SuperMeta, TagList>::sequenced_index(const boost::multi_index::detail::sequenced_index<SuperMeta, TagList>&) [with SuperMeta = boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, TagList = boost::mpl::vector0<mpl_::na>]’ is protected > /home/yabo/dev/boost/usr/include/boost/foreach.hpp:571:9: error: within this context > /home/yabo/dev/boost/usr/include/boost/multi_index/sequenced_index.hpp: In copy constructor ‘boost::foreach_detail_::simple_variant<T>::simple_variant(const boost::foreach_detail_::simple_variant<T>&) [with T = boost::multi_index::detail::sequenced_index<boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, boost::mpl::vector0<mpl_::na> >, boost::foreach_detail_::simple_variant<T> = boost::foreach_detail_::simple_variant<boost::multi_index::detail::sequenced_index<boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, boost::mpl::vector0<mpl_::na> > >]’: > /home/yabo/dev/boost/usr/include/boost/foreach.hpp:256:8: instantiated from ‘boost::foreach_detail_::auto_any<boost::foreach_detail_::simple_variant<T> > boost::foreach_detail_::contain(const T&, bool*) [with T = boost::multi_index::detail::sequenced_index<boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, boost::mpl::vector0<mpl_::na> >]’ > bmi.cc:28:3: instantiated from here > /home/yabo/dev/boost/usr/include/boost/multi_index/sequenced_index.hpp:549:3: error: ‘boost::multi_index::detail::sequenced_index<SuperMeta, TagList>::sequenced_index(const boost::multi_index::detail::sequenced_index<SuperMeta, TagList>&) [with SuperMeta = boost::multi_index::detail::nth_layer<1, int, boost::multi_index::indexed_by<boost::multi_index::sequenced<> >, std::allocator<int> >, TagList = boost::mpl::vector0<mpl_::na>]’ is protected > /home/yabo/dev/boost/usr/include/boost/foreach.hpp:578:13: error: within this context Note that with clang++ 2.9 the code doesn't compile at all either with Boost 1.46 or Boost 1.47. Thanks! -- Maxime

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[Concept] Ignoring return types
by Robert Jones 03 Aug '11

03 Aug '11

I have a template that I instantiate with a type that has to be nullary callable, so template <typename NullaryCallable> struct X { /*....*/ }; I'd like to be a good boy scout here, so I should constrain the template parameter, so template <typename NullaryCallablle> struct X { BOOST_CONCEPT_ASSERT(( Generator<NullaryCallable, void> )); // ... }; However, that constrains it to be nullary callable and returning void, and I'd prefer to avoid the void condition. Is all that sensible, true, and fixable? Thx - Rob.

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#define BOOST_ASSERT_MSG_OSTREAM std::cout - message is not displayed
by asif saeed 03 Aug '11

03 Aug '11

Hi, After I have #defined BOOST_ASSERT_MSG_OSTREAM std::cout, using BOOST_ASSERT_MSG with a customized message does not display the message and, instead, I get the following message from Visual C++ 2010 Express: R6010 Abort() has been called What can I do to display the customized message? Best, Asif

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Boost Book - comments?
by Robert Jones 03 Aug '11

03 Aug '11

Morning All Does anyone have any knowledge of this book? http://www.amazon.co.uk/Boost-C-Libraries/dp/3639942310/ref=sr_1_7?s=books&… <http://www.amazon.co.uk/Boost-C-Libraries/dp/3639942310/ref=sr_1_7?s=books&…>It's genesis, currency, provenance, and possibly a few review-like comments? Thx - Rob.

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Re: [Boost-users] boost.regex with ICU memory cleanup on windows
by Alex Perry 03 Aug '11

03 Aug '11

John Maddock wrote on Tue, 2 Aug 2011 12:14:53 +0100 > There are a number of issues here: > > 1) Your call to u_cleanup() occurs while a u32regex object is still in existence, > so any ICU data being cached is actually still being used at that point. I couldn't get u_cleanup() to work anywhere - ie BOOST_AUTO_TEST_CASE( u32_regex ) { { boost::u32regex re( boost::make_u32regex("\\d{3}")); } u_cleanup(); } Or having u_cleanup() in a fixture teardown (which is how it was in the original code) doesn't seem to make any difference > 2) Boost.Regex does cache some internal data for improved performance - > this is relatively small and gets cleared after main() exits. > 3) Point (2) means that a call to _CrtDumpMemoryLeaks() before main exits > will report leaks, where as using something like: > > struct cleanup > { > ~cleanup() > { > _CrtDumpMemoryLeaks(); > } > }; > > cleanup c; The boost unit test framework does appear to do the memory dump in a destructor of a static object - I guess whether the regex library statics are destructed first depends on the order of loading - not sure if there is any easy way of ensuring that the unit test framework is destructed last (perhaps if I link to UTF as a static library?). > 4) Other leak detectors such as valgrind and VLD report no errors (and give > much more useful reports than the brain-dead MS ones IMO). > > HTH, John. :-) yes I agree - my current solution is --detect_memory_leaks=0 when running the unit tests - which at least stops the report. I was hoping that this was a reasonably common issue and there was some clean up function (like u_cleanup()) specifically for the regex library but if not can live with switching off memory loss detection. Thanks a lot for the help here though - it is much appreciated. Alex

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Re: [Boost-users] [Repost][Boost][Serialization] ASSERTtriggered during reading 1.40 binary archive w/ Boost 1.47
by marc.viala＠sfr.fr 03 Aug '11

03 Aug '11

> De la part de Pfligersdorffer, Christian > > We were facing similar problems jumping from 1.36 to 1.45. > Binary archive backwards compatibility is broken in a few places. > > But: it is fixable. We may provide a patch Thanks Christian for your reply to this annoying issue. If you confirm that the backward compatibility is broken for Boost.Serialization #1.40 to #1.47 then *Yes* I would really appreciate any king of patch to address this issue. Looking the Boost.Serialization code, my first feeling would be to patch the implementation of basic_binary_iarchive::load_override(class_id_type & t, int version) for the library_version_type(5) ('5' stands for the library version for the release #1.40) but maybe this patch is too naïve and insufficient. If you can send me back a patch for this issue, I'll use it ASAP. > is there a TRAK ticket? I'm not sure but the ticket #5567 (https://svn.boost.org/trac/boost/ticket/5567) seems to address this bug. Thanks in advance and best regards, Marc Viala

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Re: [Boost-users] [Repost][Boost][Serialization] ASSERT triggeredduring reading 1.40 binary archive w/ Boost 1.47
by Pfligersdorffer, Christian 03 Aug '11

03 Aug '11

We were facing similar problems jumping from 1.36 to 1.45. Binary archive backwards compatibility is broken in a few places. But: it is fixable. We may provide a patch - is there a TRAK ticket? Regards, -- Christian Pfligersdorffer Software Engineering www.eos.info > -----Ursprüngliche Nachricht----- > Von: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] Im Auftrag von > Marc Perso > Gesendet: Mittwoch, 3. August 2011 07:30 > An: boost-users(a)lists.boost.org > Betreff: [Boost-users] [Repost][Boost][Serialization] ASSERT triggeredduring reading 1.40 binary archive > w/ Boost 1.47 > > Let me forward this message posted few days ago since nobody has confirmed > that the issue described hereafter exists. I would really appreciate if > someone could take a look (maybe Mr Robert Ramey) and give some advice on > this subject. > > Best regards, > > Marc Viala > > ------------------------------------------------------------------------ > > Hello Booster, > > We are trying to jump from Boost 1.40 to Boost 1.47 but we are facing an > issue: an ASSERT is raised in debug mode when reading back binary archive > generated by Boost.Serialization 1.40 with the Boost.Serialization 1.47. > This ASSERT is at line 116 in basic_archive.hpp: > > BOOST_ASSERT(t_ <= boost::integer_traits<base_type>::const_max) > > And it occurs with the following platform: MSVC 8.0 and Windows XP/32bits or > Win7/64bits. > > Looking at the load_override and save_override implementations for > class_id_type in #1.40, they seem loading and saving an 'int_least16_t' > (equiv. to a short for our platform) while load_override(class_id_type) for > #1.47 attempts to read an 'int' (file: basic_binary_iarchive.hpp @ line 98). > > My questions are: > - This assert suggests that we can't read back previous binary archives > (#1.40 at least) with Boost.Serialization 1.47, is this a known pending > issue for Boost.Serialization? > > - If yes, how we can manage that and how we can complete the migration to > 1.47 in our case (it should be noted that we must be able to read back our > 1.40 binary archives)? Is there any known patch for this problem? > > Any assistance will be greatly appreciated. > > Best regards, > > Marc Viala > > PS: I'm not sure but ticket #5567 seems already opened on this issue but has > not been yet fixed (https://svn.boost.org/trac/boost/ticket/5567) > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users

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Boost.Tokenizer / Sep - Compile-time errors ...
by asif saeed 03 Aug '11

03 Aug '11

Hi, Here is a piece of code that _only_ works when I provide it a hard-coded constant ";": typedef boost::char_separator<char_type_t> sep_type_t; typedef boost::tokenizer<sep_type_t> tokenizer_t; sep_(pa_->separator_.c_str()), t_(messageString,sep_), i_(t_.begin()) It wouldn't work with the separator passed in a variable (pa_->separator.c_str()). Tokenizer wouldn't work even if I initialize a const char* with a ";" and then pass that const char *variable to sep_ above. It gives me the following errors on if I pass separator in a variable: error C2780: 'bool boost::char_separator<Char>::operator ()(InputIterator &,InputIterator,Token &)' : expects 3 arguments - 1 provided Any idea how I can pass it a separator in a variable? Best, Asif

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