October 2015 - Boost-users - lists.preview.boost.org

Re: [Boost-users] [interprocess] Interprocess mutex not working / throwing exception when trying to write lock
by nav999 19 Oct '15

19 Oct '15

Dear Admin, It's ok if this does not reach the mailing list. I'm putting it up here as the answer, so that anyone browsing this Nabble forum will find it. The answer is here: http://stackoverflow.com/questions/33197889/boost-interprocess-mutex-crashe… -- View this message in context: http://boost.2283326.n4.nabble.com/interprocess-Interprocess-mutex-not-work… Sent from the Boost - Users mailing list archive at Nabble.com.

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[intrusive] accessing the hook type?
by Oliver Kowalke 18 Oct '15

18 Oct '15

I'd like to determine the hook type of an intrusive container (intrusive::list): template< typename List > void do_link( List & lst) { static_assert(std::is_same< typename List::???, my_hook_type >::value); lst.push_back( * this); }

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boost spirit qi/karma char parsing/generating
by Ernest Zaslavsky 18 Oct '15

18 Oct '15

The question why does it treated as string character when my intention is to work with 8bit integral type? int8_t/uint8_t does not help either on most platforms it is just a define for signed/unsigned char. So, the broader question, how do you work with “byte” type when it is always treated as character? And the main question how do I force qi/karma to treat “char” as a number? P.S. cast to short is an obvious solution but it is not elegant [Read More]<http://feeds.feedburner.com/~r/sizmek-blog/~6/1> [http://www.sizmek.com/Sizmek.png]<http://www.sizmek.com/>

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Boost.Python extension
by Jeff Archer 16 Oct '15

16 Oct '15

I am trying to use Boost.python to create a python extension. I have created the hello_ext example but find that I cannot import it. I am always getting the error "ImportError: No module named 'hello_ext'". Boost 1.59.0 Python 3.5 Visual Studio 2015

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Re: [Boost-users] [interprocess] Interprocess mutex not working / throwing exception when trying to write lock
by Malko 16 Oct '15

16 Oct '15

Copying over here my initial reply: Hi, 1. Your lockWithWriteLock and lockWithReadLock create a lock, which locks on construction and unlocks on destruction, hence when the function returns no lock is held on the mutex. 2. The fact that you put a scope here makes me think that your intention is for the lock to be unlocked at the end of this scope (which it won't, as it is unlocked way before, as per #1). { std::cout<<"Program 1: Before first locking -------------------------- 1 v\n"; temp.sharedMutex->lockWithWriteLock(); const unsigned int SLEEP_TIME_IN_SECOND = 60; std::cout<<"Program 1: sleep for "<< SLEEP_TIME_IN_SECOND << "\n"; sleep(SLEEP_TIME_IN_SECOND); std::cout<<"Program 1: Finished sleeping\n"; } In this case though, you would perform the wait in bold while still holding the lock, and hence preventing the 2nd program from locking it. Once out of the scope you destroy the object right away. NOTE: both the issue in #1 and #2 lead to your first program possibly deleting the mutex before the 2nd program is done with it. Which leads to the issue you are experiencing. 3. If you need to have the 1st program wait for the 2nd program to be done, then do not use sleeps, use a condition_variable. -- View this message in context: http://boost.2283326.n4.nabble.com/interprocess-Interprocess-mutex-not-work… Sent from the Boost - Users mailing list archive at Nabble.com.

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[Thread] Problems compiling an example from the docs
by Malko 16 Oct '15

16 Oct '15

Hi, I am trying to compile the following example: http://www.boost.org/doc/libs/1_59_0/doc/html/thread/synchronization.html#t… #include <boost/thread.hpp> #include <boost/thread/future.hpp> int parallel_sum(int* data, int size) { int sum = 0; if ( size < 1000 ) for ( int i = 0; i < size; ++i ) sum += data[i]; else { boost::future<int> handle = boost::async(parallel_sum, data+size/2, size-size/2); sum += parallel_sum(data, size/2); sum += handle.get(); } return sum; } int main() { int data[] = {1,2,3,4,5,6,7,8,9,10}; int a(parallel_sum, data, 10); return 0; } It does not compile because future is not a type in boost and async has the wrong signature. The future error goes away by defining BOOST_THREAD_PROVIDES_FUTURE, but I can not find this mentioned anywhere in the docs, I found out only looking on stack overflow. The async signature seems to require a function of arity 0. This is clang 3.4 output using Boost.1.59 and C++03: XXX/src/futtest.cpp:12:33: error: no matching function for call to 'async' boost::future<int> handle = boost::async(parallel_sum, data+size/2, size-size/2); ^~~~~~~~~~~~ /home/dev/build/third_party/64-rhel5/boost_1_59_0/include/boost/thread/future.hpp:3545:3: note: candidate function template not viable: requires 2 arguments, but 3 were provided async(launch policy, R(*f)()) { ^ /home/dev/build/third_party/64-rhel5/boost_1_59_0/include/boost/thread/future.hpp:3609:3: note: candidate function template not viable: requires 2 arguments, but 3 were provided async(launch policy, BOOST_THREAD_FWD_REF(F) f) { ^ /home/dev/build/third_party/64-rhel5/boost_1_59_0/include/boost/thread/future.hpp:3961:3: note: candidate function template not viable: requires single argument 'f', but 3 arguments were provided async(R(*f)()) { ^ /home/dev/build/third_party/64-rhel5/boost_1_59_0/include/boost/thread/future.hpp:3978:3: note: candidate function template not viable: requires single argument 'f', but 3 arguments were provided async(BOOST_THREAD_FWD_REF(F) f) { ^ XXX/src/futtest.cpp:22:7: error: excess elements in scalar initializer Is there more macro to be used to enable this to compile? Thanks P.S. It would be nice to have all the info about macro configuration for future (and async, if it has any) in the docs. -- View this message in context: http://boost.2283326.n4.nabble.com/Thread-Problems-compiling-an-example-fro… Sent from the Boost - Users mailing list archive at Nabble.com.

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Xpressive regex superscript 2 and 3 parsed as plain digits
by Mia 15 Oct '15

15 Oct '15

Help pleaseI am using xpressive for text processing with regexes.Microsoft Visual C++ 13.0 on a windows 10 laptop, boost version 1_59_0 (and lib64-msvc-12.0 downloaded from sourceforge) , locale is en_US.UTF-8 .my regular expressions for catching any and all digits :wsregex any_number_regex = wsregex::compile(L"^(.*\\D)?(\\d+)(\\D.*)?$");Looks like it recognizes the superscript 2 and superscript 3 as plain “digits”all other superscript digits are not caught by this regex.examples:πr² 234³is this intentional?is this a bug?(I know I can change the regex to catch [0-9]+, this regex just one of many I use in my software!)thank youMia -- View this message in context: http://boost.2283326.n4.nabble.com/Xpressive-regex-superscript-2-and-3-pars… Sent from the Boost - Users mailing list archive at Nabble.com.

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Use of uninitialized value in any_range
by Auer, Jens 15 Oct '15

15 Oct '15

Hi, Valgrind reports multiple problems in our project which seem to come from boost::range::any_range. I was able to produce a small example which reproduces the problem: #include <iostream> #include <boost/range.hpp> #include <boost/range/any_range.hpp> #include <boost/range/adaptors.hpp> struct Int { Int(int i): x(i) {} int x; }; int main( int argc, char* argv[] ) { typedef boost::any_range<Int*, boost::forward_traversal_tag, Int*, std::ptrdiff_t> R; std::vector<std::unique_ptr<Int>> v; v.push_back( std::make_unique<Int>(42) ); auto f = [](std::unique_ptr<Int> const& p) {return p.get();}; R r = v | boost::adaptors::transformed(f); auto x = (*boost::begin(r))->x; std::cout << x << std::endl; return 0; } Running this, valgrind reports a "Use of uninitialized value of size 8": # g++ --version g++ (GCC) 5.2.0 # g++ -std=c++1y -o test test.cpp # valgrind --version valgrind-3.11.0 # valgrind --track-origins=yes ./test ==8119== Memcheck, a memory error detector ==8119== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al. ==8119== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info ==8119== Command: ./test ==8119== ==8119== Use of uninitialised value of size 8 ==8119== at 0x4010B8: main (in /tmp/test) ==8119== Uninitialised value was created by a stack allocation ==8119== at 0x40315D: boost::range_detail::any_iterator<Int*, boost::iterators::forward_traversal_tag, Int*, long, boost::any_iterator_buffer<64ul> >::dereference() const (in /tmp/test) ==8119== 42 ==8119== ==8119== HEAP SUMMARY: ==8119== in use at exit: 72,704 bytes in 1 blocks ==8119== total heap usage: 3 allocs, 2 frees, 72,716 bytes allocated ==8119== ==8119== LEAK SUMMARY: ==8119== definitely lost: 0 bytes in 0 blocks ==8119== indirectly lost: 0 bytes in 0 blocks ==8119== possibly lost: 0 bytes in 0 blocks ==8119== still reachable: 72,704 bytes in 1 blocks ==8119== suppressed: 0 bytes in 0 blocks ==8119== Rerun with --leak-check=full to see details of leaked memory ==8119== ==8119== For counts of detected and suppressed errors, rerun with: -v ==8119== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 1 from 1) Best wishes, Jens -- Jens Auer | CGI | Software-Engineer CGI (Germany) GmbH & Co. KG Rheinstraße 95 | 64295 Darmstadt | Germany T: +49 6151 36860 154 jens.auer(a)cgi.com<mailto:jens.auer@cgi.com> Unsere Pflichtangaben gemäß § 35a GmbHG / §§ 161, 125a HGB finden Sie unter de.cgi.com/pflichtangaben<http://de.cgi.com/pflichtangaben>. CONFIDENTIALITY NOTICE: Proprietary/Confidential information belonging to CGI Group Inc. and its affiliates may be contained in this message. If you are not a recipient indicated or intended in this message (or responsible for delivery of this message to such person), or you think for any reason that this message may have been addressed to you in error, you may not use or copy or deliver this message to anyone else. In such case, you should destroy this message and are asked to notify the sender by reply e-mail. -- Jens Auer | CGI | Software-Engineer CGI (Germany) GmbH & Co. KG Rheinstraße 95 | 64295 Darmstadt | Germany T: +49 6151 36860 154 jens.auer(a)cgi.com<mailto:jens.auer@cgi.com> Unsere Pflichtangaben gemäß § 35a GmbHG / §§ 161, 125a HGB finden Sie unter de.cgi.com/pflichtangaben<http://de.cgi.com/pflichtangaben>. CONFIDENTIALITY NOTICE: Proprietary/Confidential information belonging to CGI Group Inc. and its affiliates may be contained in this message. If you are not a recipient indicated or intended in this message (or responsible for delivery of this message to such person), or you think for any reason that this message may have been addressed to you in error, you may not use or copy or deliver this message to anyone else. In such case, you should destroy this message and are asked to notify the sender by reply e-mail.

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Boost Python having trouble with C++ int return results
by Bradley Neuberg 15 Oct '15

15 Oct '15

I'm fairly new to using Boost Python and running into some funkiness. When I try to pass back a simple int from C++ to Python, I get a Segmentation Fault. Here's the C++: #include <iostream> #include <boost/python.hpp> int helloworld() { return 10; } BOOST_PYTHON_MODULE(test_boost) { boost::python::def("helloworld", helloworld); } and here's the Python: import test_boost print(test_boost.helloworld()) The strange thing is it works fine with char const* types. Does anyone know what could cause this? Compiled on Mac OS X 10.10.5 with Anaconda Python with the following: g++ -g -shared -fPIC -I/Users/bradneuberg/anaconda/include/python2.7 test_boost.cpp -lpython2.7 -lboost_python -o test_boost.so Best, Brad Neuberg

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Boost Intrusive compiler error
by Davies, John 14 Oct '15

14 Oct '15

I've been using Boost 1.55.0 that I built myself for about a year. Our team decide that we would prefer to use the pre-built files located on SourceForge as a standard (http://sourceforge.net/projects/boost/files/boost-binaries/1.55.0-build2/ ) I downloaded and installed and changed my Visual Studio 2013 project to point to the new root folder. I'm getting this error: Error 2 error C2228: left of '.select_on_container_copy_construction' must have class/struct/union c:\boostlib\boost\intrusive\detail\has_member_function_callable_with.hpp 200 1 BoostCommunication Googling hasn't helped. This code compiled on the libraries I built. I'd appreciate any help in tracking this down. ________________________________ The information contained in this message may be confidential and legally protected under applicable law. The message is intended solely for the addressee(s). If you are not the intended recipient, you are hereby notified that any use, forwarding, dissemination, or reproduction of this message is strictly prohibited and may be unlawful. If you are not the intended recipient, please contact the sender by return e-mail and destroy all copies of the original message.

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