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Spherical Bessel function (nu, x as real) implementation
by campagne 26 Feb '16

26 Feb '16

Dear developpers, 1) Does you use this reference to compute Spherical Bessel Functions for real argument? Accurate recursive generation of spherical Bessel and Neumann functions for a large range of indices E. Gillman <http://scitation.aip.org/content/contributor/AU0510272>^1 and H. R. Fiebig <http://scitation.aip.org/search?value1=H.+R.+Fiebig&option1=author&option91…>Comput. Phys. 2, 62(1988); http://dx.doi.org/10.1063/1.168296 2) is there a way to speed up the computation of j_nu(x) if one wants 10 digits accuracy for instance? Best regards J.E

2 1

[ASIO] Resolver question
by Davies, John 25 Feb '16

25 Feb '16

I have some pretty simple UPD code. (It has to be simple, I'm new at ASIO) boost::asio::ip::udp::resolver::query query(boost::asio::ip::udp::v4(), addr, port); m_receiverEndpoint = *m_resolver.resolve(query); If my address is 192.168.1.112 everything works If my address is 192.168.001.112 it doesn't work and throws an exception about not finding the host. It's not a big deal, but it sure took me a long time to track down. Is there some sort of Boost magic I can do to convert the bad address into a good address? Thanks, John ________________________________ 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.

6 11

Boost Thread Compile Issue
by Len Za 25 Feb '16

25 Feb '16

When simply including into C++ project and attempting to compile causes the following compile error: Environment: - Visual Studio 2010 Pro (Project Configuration: DLL project) - boost v1.60.0 C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(99): error C2146: syntax error : missing ';' before identifier 'curr' C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(81) : while compiling class template member function 'boost::posix_time::ptime boost::date_time::microsec_clock<time_type>::create_time(boost::date_time::microsec_clock<time_type>::time_converter)' with [ time_type=boost::posix_time::ptime ] C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/thread/thread_time.hpp(22) : see reference to class template instantiation 'boost::date_time::microsec_clock<time_type>' being compiled with [ time_type=boost::posix_time::ptime ] C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(99): error C2065: 'curr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(100): error C2065: 'curr_ptr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(100): error C2065: 'curr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(101): error C2065: 'curr_ptr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(101): error C2227: left of '->tm_year' must point to class/struct/union/generic type type is ''unknown-type'' C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(102): error C2065: 'curr_ptr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(102): error C2227: left of '->tm_mon' must point to class/struct/union/generic type type is ''unknown-type'' C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(103): error C2065: 'curr_ptr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(103): error C2227: left of '->tm_mday' must point to class/struct/union/generic type type is ''unknown-type'' C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(111): error C2065: 'curr_ptr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(111): error C2227: left of '->tm_hour' must point to class/struct/union/generic type type is ''unknown-type'' C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(112): error C2065: 'curr_ptr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(112): error C2227: left of '->tm_min' must point to class/struct/union/generic type type is ''unknown-type'' C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(113): error C2065: 'curr_ptr' : undeclared identifier C:\src\SDK\Boost\boost_1_60_0\boost_1_60_0\boost/date_time/microsec_time_clock.hpp(113): error C2227: left of '->tm_sec' must point to class/struct/union/generic type type is ''unknown-type''

1 0

(no subject)
by Виктория Доможакова 24 Feb '16

24 Feb '16

Hello. I have template class. I want to serialize it. But I don't know how. template <class T> class AverDayVisTask : public DrawTask, public AverDayVisMathTask <T> { public: // some functions private: friend class boost::serialization::access; //! boost::serialize template <class Archive> void serialize(Archive& ar, const unsigned int /*version*/) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(DrawTask); ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(AverDayVisMathTask<T>); //<----- error } }; // class AverDayVisTask BOOST_CLASS_VERSION(AverDayVisTask<SphericalModel>, 1); BOOST_CLASS_VERSION(AverDayVisTask<SphericalNutModel>, 1); BOOST_CLASS_VERSION(AverDayVisTask<WGS84Model>, 1); BOOST_CLASS_IMPLEMENTATION(AverDayVisTask<SphericalModel>, boost::serialization::object_class_info); BOOST_CLASS_IMPLEMENTATION(AverDayVisTask<SphericalNutModel>, boost::serialization::object_class_info); BOOST_CLASS_IMPLEMENTATION(AverDayVisTask<WGS84Model>, boost::serialization::object_class_info); How fix my problem? -- Виктория Доможакова

2 1

[graph] abort algorithm execution from a visitor
by Frank Tetzel 23 Feb '16

23 Feb '16

Hi all, i played around with the bfs example calculating distances to all vertices. Now i just want to calculate the distance between two vertices, so i want to stop when the target vertex is visited. If i understood the visitor concept correctly it's not really possible to change the behaviour of the algorithm from a visitor. Does anybody know of any workaround to do early exit? Do i have to implement a new algorithm for this? In a different thread on this list Paolo Bolzoni wrote that he aborts in a custom visitor by throwing an exception. Is this the only way? I'm using bfs here and not dijkstra because i have uniform edge weights. Btw, if someone could fix the documentation that would be really nice: http://www.boost.org/doc/libs/1_60_0/libs/graph/doc/bfs_visitor.html The code snippet there did not work for me. I had to wrap make_bfs_visitor() in visitor() like it is done in examples/bfs.cpp too. Regards, Frank

2 2

Boost 1.60 Raspberry Pi lockfree::queue compilation error
by Alexander Simpson 23 Feb '16

23 Feb '16

Hello, I’m trying to compile a project that makes use of boost::lockfree::queue on a Raspberry Pi 2 running Jessie. I built version 1.60 of Boost myself (apt-get was out of date) with sudo ./bjam install. I’m not cross-compiling. When I attempt to compile a project that uses the boost library I get the error listed below (where boostreader.cpp is the file written by me). I found a patch suggested two years ago here (https://svn.boost.org/trac/boost/ticket/9041 <https://svn.boost.org/trac/boost/ticket/9041>) but the changes in that patch seem to have already applied in 1.60, so I’m at a loss as to what to do. Assistance would be greatly appreciated. Alexander Simpson Error message: In function `boost::lockfree::detail::freelist_stack<boost::lockfree::queue<int, boost::parameter::void_, boost::parameter::void_, boost::parameter::void_>::node, std::allocator<boost::lockfree::queue<int, boost::parameter::void_, boost::parameter::void_, boost::parameter::void_>::node> >::~freelist_stack()': main.cpp:(.text._ZN5boost8lockfree6detail14freelist_stackINS0_5queueIiNS_9parameter5void_ES5_S5_E4nodeESaIS7_EED2Ev[_ZN5boost8lockfree6detail14freelist_stackINS0_5queueIiNS_9parameter5void_ES5_S5_E4nodeESaIS7_EED5Ev]+0x18): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree6detail14freelist_stackINS0_5queueIiNS_9parameter5void_ES5_S5_E4nodeESaIS7_EED2Ev[_ZN5boost8lockfree6detail14freelist_stackINS0_5queueIiNS_9parameter5void_ES5_S5_E4nodeESaIS7_EED5Ev]+0x24): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.o: In function `boost::lockfree::queue<int, boost::parameter::void_, boost::parameter::void_, boost::parameter::void_>::queue(unsigned int)': main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0x6c): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0x78): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0xb0): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0xbc): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0xd8): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0xe4): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0x148): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0x170): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0x1ec): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0x1f8): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0x224): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC2Ej[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_EC5Ej]+0x230): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.o: In function `boost::lockfree::queue<int, boost::parameter::void_, boost::parameter::void_, boost::parameter::void_>::~queue()': main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x58): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x64): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x90): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x9c): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0xc8): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0xd4): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x128): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x134): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x164): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x170): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x180): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x18c): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x1c8): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x1d4): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x1e8): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x1f4): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x218): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x224): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x260): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x26c): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x278): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' main.cpp:(.text._ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED2Ev[_ZN5boost8lockfree5queueIiNS_9parameter5void_ES3_S3_ED5Ev]+0x284): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' boostreader.o: In function `BoostReader::run()': boostreader.cpp:(.text+0x84): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' boostreader.cpp:(.text+0x90): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' boostreader.cpp:(.text+0xb8): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' boostreader.cpp:(.text+0xc4): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' boostreader.cpp:(.text+0xf0): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' boostreader.cpp:(.text+0xfc): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' boostreader.cpp:(.text+0x11c): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' boostreader.cpp:(.text+0x128): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' boostreader.cpp:(.text+0x1ac): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' boostreader.cpp:(.text+0x1dc): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' boostreader.cpp:(.text+0x204): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' boostreader.cpp:(.text+0x210): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' boostreader.cpp:(.text+0x264): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' boostreader.cpp:(.text+0x288): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()' boostreader.cpp:(.text+0x438): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::scoped_lock(void const volatile*)' boostreader.cpp:(.text+0x454): undefined reference to `boost::atomics::detail::lockpool::scoped_lock::~scoped_lock()'

2 1

boost 1.54: problem with building documentation.
by Paul K 22 Feb '16

22 Feb '16

Hallo people. I need to have documentation in man pages format on my ubuntu 14.04. Unfortunatelly, I fail with this task. The following are the steps I've performed. In step 11 I do "../b2" instead "../b2 man" just to highlight that the problem is not related to building the man pages. Of course "../b2 man" fails as well Could You please help me with it? 1. install following packages for man pages build. lubuntu.14.04$ sudo apt-get install xsltproc lubuntu.14.04$ sudo apt-get install doxygen 2. lubuntu.14.04$ dpkg --list | grep libboost-all ii libboost-all-dev 1.54.0.1ubuntu1 i386 Boost C++ Libraries development files (ALL) (default version) 3. download boost_1_54_0.tar.bz2, unpack to ~/ 4. cd ~/boost_1_54_0 5. ./bootstrap prepares build configuration and puts it to project-config.jam. 6. ./b2 builds whole the boost libraries, but does not install them into the system. 7. lubuntu.14.04$ export BOOST_ROOT=/home/userp/boost_1_54_0 8. lubuntu.14.04$ cd ~/boost.doc/ 9. lubuntu.14.04$ ~/boost_1_54_0/tools/boostbook/setup_boostbook.sh Downloading DocBook XSLT Stylesheets version 1.75.2... Expanding DocBook XSLT Stylesheets into /home/userp/boost.doc/docbook-xsl-1.75.2...done. Downloading DocBook XML DTD version 4.2... Expanding DocBook XML DTD into /home/userp/boost.doc/docbook-dtd-4.2... done. Searching for xsltproc... /usr/bin/xsltproc. Searching for Doxygen... /usr/bin/doxygen. Searching for Java... /usr/bin/java. Downloading FOP distribution version 0.94... Expanding FOP distribution into /home/userp/boost.doc/fop-0.94... done. Updating Boost.Jam configuration in /home/userp/user-config.jam... done. Done! Execute "bjam --v2" in a documentation directory to generate documentation with BoostBook. If you have not already, you will need to compile Boost.Jam. 10. lubuntu.14.04$ cd ~/boost_1_54_0/doc 11. lubuntu.14.04$ ../b2 Performing configuration checks - has_icu builds : yes (cached) /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:1099: in virtual-target.register-actual-name from module virtual-target error: Duplicate name of actual target: <p../bin.v2/libs/filesystem/build/gcc-4.9.3/release/link-static>libboost_filesystem.a error: previous virtual target { gcc%gcc.archive-libboost_filesystem.a.STATIC_LIB { gcc%gcc.compile.c++-codecvt_error_category.o.OBJ { codecvt_error_category.cpp.CPP } } { gcc%gcc.compile.c++-operations.o.OBJ { operations.cpp.CPP } } { gcc%gcc.compile.c++-path.o.OBJ { path.cpp.CPP } } { gcc%gcc.compile.c++-path_traits.o.OBJ { path_traits.cpp.CPP } } { gcc%gcc.compile.c++-portability.o.OBJ { portability.cpp.CPP } } { gcc%gcc.compile.c++-unique_path.o.OBJ { unique_path.cpp.CPP } } { gcc%gcc.compile.c++-utf8_codecvt_facet.o.OBJ { utf8_codecvt_facet.cpp.CPP } } { gcc%gcc.compile.c++-windows_file_codecvt.o.OBJ { windows_file_codecvt.cpp.CPP } } } error: created from ../libs/filesystem/build/boost_filesystem error: another virtual target { gcc%gcc.archive-libboost_filesystem.a.STATIC_LIB { gcc%gcc.compile.c++-codecvt_error_category.o.OBJ { codecvt_error_category.cpp.CPP } } { gcc%gcc.compile.c++-operations.o.OBJ { operations.cpp.CPP } } { gcc%gcc.compile.c++-path.o.OBJ { path.cpp.CPP } } { gcc%gcc.compile.c++-path_traits.o.OBJ { path_traits.cpp.CPP } } { gcc%gcc.compile.c++-portability.o.OBJ { portability.cpp.CPP } } { gcc%gcc.compile.c++-unique_path.o.OBJ { unique_path.cpp.CPP } } { gcc%gcc.compile.c++-utf8_codecvt_facet.o.OBJ { utf8_codecvt_facet.cpp.CPP } } { gcc%gcc.compile.c++-windows_file_codecvt.o.OBJ { windows_file_codecvt.cpp.CPP } } } error: created from ../libs/filesystem/build/boost_filesystem error: added properties: <auto-index-internal>off <auto-index-no-duplicates>off <auto-index-section-names>on <auto-index-verbose>off <auto-index>off <format>docbook error: removed properties: <format>html /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:484: in actualize-no-scanner from module object(file-target)@3468 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:134: in class(a)virtual-target.actualize from module object(file-target)@3468 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:815: in actualize-source-type from module object(action)@3786 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:836: in actualize-sources from module object(action)@3786 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:776: in class(a)action.actualize from module object(action)@3786 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:311: in actualize-action from module object(file-target)@3787 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:493: in actualize-no-scanner from module object(file-target)@3787 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:134: in class(a)virtual-target.actualize from module object(file-target)@3787 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:815: in actualize-source-type from module object(action)@3793 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:834: in actualize-sources from module object(action)@3793 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:776: in class(a)action.actualize from module object(action)@3793 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:311: in actualize-action from module object(file-target)@3794 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:493: in actualize-no-scanner from module object(file-target)@3794 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:134: in class(a)virtual-target.actualize from module object(file-target)@3794 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:815: in actualize-source-type from module object(action)@7122 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:834: in actualize-sources from module object(action)@7122 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:776: in class(a)action.actualize from module object(action)@7122 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:311: in actualize-action from module object(file-target)@7123 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:493: in actualize-no-scanner from module object(file-target)@7123 /home/userp/boost_1_54_0/tools/build/v2/build/virtual-target.jam:134: in class(a)virtual-target.actualize from module object(file-target)@7123 /home/userp/boost_1_54_0/tools/build/v2/build-system.jam:720: in load from module build-system /home/userp/boost_1_54_0/tools/build/v2/kernel/modules.jam:289: in import from module modules /home/userp/boost_1_54_0/tools/build/v2/kernel/bootstrap.jam:139: in boost-build from module /home/userp/boost_1_54_0/boost-build.jam:17: in module scope from module regards

1 0

boost::any constructors
by David 22 Feb '16

22 Feb '16

Hi, boost::any has a perfect forward constructor declared as: template<typename ValueType> any(ValueType&& value , typename boost::disable_if<boost::is_same<any&, ValueType> >::type* = 0 // disable if value has type `any&` , typename boost::disable_if<boost::is_const<ValueType> >::type* = 0) // disable if value has type `const ValueType&&` : content(new holder< typename decay<ValueType>::type >(static_cast<ValueType&&>(value))) {} The is_const SFINAE exclusion forces const types to the regular copy constructor: template<typename ValueType> any(const ValueType & value) : content(new holder< BOOST_DEDUCED_TYPENAME remove_cv<BOOST_DEDUCED_TYPENAME decay<const ValueType>::type>::type >(value)) {} What is different about how the regular copy constructor treats a constant value than what the perfect forward construct would do if the is_const exclusion were removed? Thanks, David

2 1

Nested BOOST_FOREACH crash
by peyman＠ausdia.com 22 Feb '16

22 Feb '16

Good Day Boosters! I am experiencing sporadic crashes that look like memory problem when I have nested (2 level) BOOST_FOREACH loops. Reason I say it looks like memory problem is because slightest change will make it crash or not crash. For example, adding a simple cout would change it! I cannot provide a testcase. So I am just wondering if anybody has experienced the same, or know what could be going on. I am using Boost 1.57. Cheers, Peyman

2 1

Need help when adapting boost 1.59.0 to WinRT
by Nguyễn Trung Duy 22 Feb '16

22 Feb '16

Dear Boost team, I need your help with adapting boost 1.59 to WinRT. I am working on boost and reSIProcate. I built boost and integrated it with reSIProcate project. However, when build reflow project, I got stuck with bellow bugs. I wonder with your great experiences, could you please give me some advice. The error happens at line 96 : #if defined(BOOST_ASIO_WINDOWS_RUNTIME) const int max_addr_v4_str_len = 256; const int max_addr_v6_str_len = 256; typedef unsigned __int32 u_long_type; typedef unsigned __int16 u_short_type; struct in4_addr_type { u_long_type s_addr; }; // error at here And the logs: *\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(96): error C3927: '->': trailing return type is not allowed after a non-function declarator (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(96): error C3484: syntax error: expected '->' before the return type (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(96): error C3613: missing return type after '->' ('int' assumed) (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(96): error C3646: 'S_addr': unknown override specifier (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C3927: '->': trailing return type is not allowed after a non-function declarator (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C3484: syntax error: expected '->' before the return type (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C3613: missing return type after '->' ('int' assumed) (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C3646: 'Byte': unknown override specifier (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C2143: syntax error: missing ',' before '[' (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C2143: syntax error: missing ')' before ';' (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C2143: syntax error: missing ';' before ')' (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/detail/socket_types.hpp(98): error C2059: syntax error: ')' (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/ip/address_v4.hpp(61): error C2039: 'S_addr': is not a member of 'default::uint32' (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/ip/address_v4.hpp(147): error C2039: 'S_addr': is not a member of 'default::uint32' (compiling source file MediaStream.cxx)\boost-msvc-14.0-store\boost/asio/ip/address_v4.hpp(153): error C2039: 'S_addr': is not a member of 'default::uint32' (compiling source file MediaStream.cxx)* Thanks you so much!!!! *--* *Best Regards,* *NGUYEN TRUNG DUY* *Android Developer* *Mobile*: (+84)977 46 12 23 *Skype :* trungduy150388 *Website*: http://nguyentrungduy.com/ *Blog*: http://dbox.nguyentrungduy.com/ *Github*: https://github.com/nguyentrungduy

2 2

Newbie
by Shan Wijesinghe 22 Feb '16

22 Feb '16

Hi all, I'm a new member to C++ boost and I have a fairly good knowledge in programming in C++. I'm very much excited to join this group and I need directions from the senior members on how to start myself. Please help me here. Thanks in advance. regards, DilSHAN.

6 11

Query on Boost.DLL
by Leo Carreon 21 Feb '16

21 Feb '16

Hi, I have been reading the Boost.DLL documentation. Can a single plugin support multiple API’s? If yes, when the multiple API’s are used at the same time; will there be only one instance of the plugin loaded or will there be multiple instances loaded? Regards, Leo

2 1

Boost.DLL
by Leo Carreon 21 Feb '16

21 Feb '16

Hi, Can anyone please let me know what the status of the Boost.DLL library is? Regards, Leo

2 1

[coroutine] - only std exceptions are caught from coroutines
by Tamas.Ruszkai＠leica-geosystems.com 21 Feb '16

21 Feb '16

3 4

[Interprocess] Communication between x86 and x64 issue
by Toni Neubert 19 Feb '16

19 Feb '16

I want to communicate between different platforms using boost interprocess. I am using vc12 and boost 1.58 on windows 7. My code below is a very simple example, that should work. But it doesn't for communications between different platforms... If I create it in x64 and open in win32, the process stuck at a lock at function try_based_lock in boost/int/sync/detail/common_algorithms.hpp In the other way around: win32 create, x64 open: the process crashes at name_length in segment_manager_helper.hpp while trying to find the name in index (priv_generic_find in segment_manager). #include <iostream> #include <boost/interprocess/managed_shared_memory.hpp> int main() { namespace bip = boost::interprocess; // open in WIN32, create in x64 #ifdef _WIN32 bip::managed_shared_memory msm(bip::open_only, "TestIPC"); #elsif X64 bip::shared_memory_object::remove("TestIPC"); bip::managed_shared_memory msm(bip::create_only, "TestIPC", 4096); msm.construct<uint32_t>("Data")[1](10); #endif // Get Data and print it auto data = msm.find<uint32_t>("Data"); if (data.second == 1) { std::cout << *data.first << std::endl; } std::cin.ignore(); return 0; } Does anybody have experience in this? Thank you in advance!

3 2

Re: [Boost-users] [Serialization] This compiles; but does it work?
by Bjorn Reese 19 Feb '16

19 Feb '16

On 02/19/2016 04:20 AM, Merrill Cornish wrote: > Can anyone tell me if this will work, or do I need to implement the > serialize() function? When you are doing different things for the input and output archives then it is better to split serialization into load and save: #include <boost/filesystem/path.hpp> #include <boost/serialization/split_free.hpp> namespace boost { namespace serialization { template <typename Archive> void serialize(Archive& ar, filesystem::path& p, const unsigned int version) { split_free(ar, p, version); } template<class Archive> void save(Archive & ar, const filesystem::path& p, unsigned int version) { ar << p.string(); } template<class Archive> void load(Archive & ar, filesystem::path& p, unsigned int version) { std::string data; ar >> data; p = data; } }}

2 1

[graph] Search algorithm using quality metric rather than distance
by rleigh＠codelibre.net 19 Feb '16

19 Feb '16

I have an adjacency_list graph (shown in attached dot file). Each edge has an attached "quality metric" as a bundled property. Similar to the dijkstra_shortest_paths algorithm, I'd like to determine the optimal path. However, this algorithm sums the distance along each edge, and finds the shortest path. What I'd like to do is *multiply* the quality metric for each edge in the path, and find the largest one. A perfect path will have a quality metric of 1.0, while suboptimal paths will have values tending towards zero, and the more "bad" edges the smaller the number. I'll likely then look at the number of edges and then select the shortest of the candidates. It seems like a simple algorithm that might already be included, but I just haven't found it yet not knowing its formal name. If anyone has any suggestions, I'd be very grateful. Many thanks, Roger

5 4

[Serialization] This compiles; but does it work?
by Merrill Cornish 19 Feb '16

19 Feb '16

mGraphFile is a data member of type boost:filesystem::path, which isn't (as I understand) handled natively by Boost Serialization. I could define template<class Archive> void serialize(Archive& ar, boost::filesystem::path& p, const unsigned int version); but it is needed in only one place. Below is an excerpt from an inline serialization function that I'm already using. While it has a redundant step not needed for loading and a different redundant step not needed for storing, it would seem to do what I need. (The minor inefficiency of the redundant statements is of no concern here.) ... std::string str = mGraphFile.string(); // redundant if loading ar & BOOST_SERIALIZATION_NVP(str); mGraphFile = str; // redundant if saving ... Can anyone tell me if this will work, or do I need to implement the serialize() function? Merrill Cornish

1 0

boost::msm usage: how to set properties of target states
by spiritwalker 18 Feb '16

18 Feb '16

States in my fsm has different properties. I define a event which will invoke a transition to a target state. I want to set properties of target by event data. My choices are: 1. set properties in the action or guard: but it is still in the source state. I fill not good if i set the target state properties at the time 2. set properties in the target entry: but the value of properties have been calculated in guard on receiving the event so i should recalculated again :( Any one can give me more ideas. Thanks ! -- View this message in context: http://boost.2283326.n4.nabble.com/boost-msm-usage-how-to-set-properties-of… Sent from the Boost - Users mailing list archive at Nabble.com.

2 1

SERIALIZE: Registering derived templete classes serialized via base ptr
by Unger, Jörg 17 Feb '16

17 Feb '16

I'm trying to serialize a derived class via a base ptr using boost serialize. The example to illustrate the problem (without templates) is as follows //****************** Main.cpp ********************** #include <fstream> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include "Derived.h" int main(int argc, char* argv[]) { std::string fileName = "Out.txt"; Derived myDerived; Base* myBasePtr = &myDerived; //myDerived.foo(); // serialize it as txt std::ofstream ofs(fileName.c_str(), std::ios_base::binary ); boost::archive::text_oarchive ota ( ofs, std::ios::binary ); //ota & boost::serialization::make_nvp(std::string("directly derived").c_str(), myDerived);; ota & boost::serialization::make_nvp(std::string("via base ptr").c_str(), myBasePtr);; return 0; } //*********************************************** //*************** Base.h ************************* #pragma once #include <boost/serialization/access.hpp> #include <boost/serialization/export.hpp> class Base { friend class boost::serialization::access; public: Base(){}; virtual ~Base(){}; template<class Archive> void serialize(Archive & ar, const unsigned int version) {}; }; BOOST_CLASS_EXPORT_KEY(Base) //*********************************************** //**************** Derived.h ********************** #pragma once #include <boost/serialization/access.hpp> #include <boost/serialization/export.hpp> #include "Base.h" class Derived : public Base { friend class boost::serialization::access; public: Derived(){}; void foo(); template<class Archive> void serialize(Archive & ar, const unsigned int version); }; BOOST_CLASS_EXPORT_KEY(Derived) //*********************************************** //**************** Derived.cpp ******************** #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include "Derived.h" //Derived::Derived() //{} void Derived::foo() { } // serializes the class template void Derived::serialize(boost::archive::text_oarchive & ar, const unsigned int version); template void Derived::serialize(boost::archive::text_iarchive & ar, const unsigned int version); template<class Archive> void Derived::serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(Base); } BOOST_CLASS_EXPORT_IMPLEMENT(Derived) //*********************************************** When compiling the above code and linking the object files, everything works fine. When I combine everything in a library (in this example it is essentially only Derived.o) and link the main file with the library, I get an error what(): unregistered class - derived class not registered or exported The problem seems to be that the registration in the linked library is not activated. The problem is simplified here, because in our implementation, the derived class is essentially a template class that does not have any cpp-files. We have just added another otherwise empty cpp file with the registration of all possible instantiations of the class. There are several possibilities to solve the problem · The macro BOOST_CLASS_EXPORT_IMPLEMENT(Derived) could be moved to the main.cpp. This workaround is not my preferred options, since the registration has to be done in every main file we want to use the library for. · The macro BOOST_CLASS_EXPORT_IMPLEMENT(Derived) could be moved to the Base.cpp (the constructor for the base class has to be implemented in this file as well). This is another option, but this requires the header files of the derived classes to be included in Base.cpp, which is not convenient either. · Serialize one object of the derived class before serialization through the pointer, but that's only a workaround. (see the commented line in Main.cpp) · Call the foo method in Main.cpp. Surprisingly, this does not depend on whether the foo function is implemented in Derived.cpp, but also if it is called in Main.cpp. Surprisingly, if "myDerived.foo();" in Main.cpp is uncommented the program works fine, which is something I do not understand. It seems that the registration is only performed, if one of the functions in this cpp file is actually called, or am I wrong? · Implement the constructor of Derived in Derived.cpp. This approach works fine for the current example (somehow similar to the previous solution). However, in our case, Derived is a template and thus the constructor can't be implemented in the cpp file. · Another option is to always link the main file with the library and the object file Derived.o, but this is also not a convenient option. · Finally, a manual registration with register_type is possible. This could be moved to a separate subroutine that is always called in different main files. What is the recommended way of registering derived template classes that are serialized through a base ptr within a library. Best regards, Jörg F. Unger

2 1

[Timer] unresolved external symbol boost::chrono::time_point
by Aman Wardak 17 Feb '16

17 Feb '16

Env: Win7 32-bit running in VirtualBox on Macbook Pro Compiler: MS Visual Studio 14 It's my first time working with Boost. I've followed the instructions here: http://www.boost.org/doc/libs/1_60_0/more/getting_started/windows.html I've compiled Boost successfully: ============================ The Boost C++ Libraries were successfully built! The following directory should be added to compiler include paths: C:\Users\IEUser\Documents\boost_1_60_0 The following directory should be added to linker library paths: C:\Users\IEUser\Documents\boost_1_60_0\stage\lib ============================================== I've added the above paths in Visual Studio and was able to run the test in step 6 of the instructions linked above to verify my environment is set up correctly. MY PROBLEM: I'm trying to compile the very first sample code at this link: http://www.boost.org/doc/libs/1_60_0/libs/timer/doc/cpu_timers.html I get the following error: ------ Build started: Project: BoostExample, Configuration: Debug Win32 ------ Source.cpp libboost_timer-vc140-mt-gd-1_60.lib(cpu_timer.obj) : error LNK2019: unresolved external symbol "public: static class boost::chrono::time_point<class boost::chrono::steady_clock,class boost::chrono::duration<__int64,class boost::ratio<1,1000000000> > > __cdecl boost::chrono::steady_clock::now(void)" (?now@steady_clock @chrono@boost@@SA?AV?$time_point@Vsteady_clock@chrono@boost@@V?$duration@ _JV?$ratio@$00$0DLJKMKAA@@boost@@@23@@23@XZ) referenced in function __catch$??1auto_cpu_timer@timer@boost@@QAE@XZ$0 C:\Users\IEUser\Documents\Visual Studio 2015\Projects\CS2370\Debug\BoostExample.exe : fatal error LNK1120: 1 unresolved externals ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== Thanks, Aman

1 0

[Test] BOOST_CHECK_EXCEPTION error message still vague
by Merrill Cornish 17 Feb '16

17 Feb '16

In BOOST_1_59_0, I complained that the error message from BOOST_CHECK_EXCEPTION was indecipherable. In BOOST_1_60_0, things improved a lot. But it still leave you hanging. I use the function fail_msg() as the predicate argument to BOOST_CHECK_EXCEPTION. If it finds a specified substring in the exception message, it returns true. Otherwise, it returns false. Below is an error message from BOOST_CHECK_EXCEPTION when the predicate returned false: exception "std::runtime_error" raised as expected: validation on the raised exception through predicate "fail_msg" The first clause says my code raised the expected exception class. That part of the message is clear and unambiguous. The second clause, however, is a non-sequitur. It seems to only acknowledge that there was a predicate named "fail_msg" without saying whether it returned true or false. Overall, the whole message doesn't say whether BOOST_CHECK_EXCEPTION passed or failed. Since a message was output, the user can assume things did not go well, but it seems like the message could be more explicit. Merrill Cornish

2 2

multiprecision max and et_on
by Daniel Brake 16 Feb '16

16 Feb '16

Hi Boost, I would like to be able to use the Eigen linear algebra library with Boost.Multiprecision with et_on. However, as noted here: https://svn.boost.org/trac/boost/ticket/11149 for max, et_on isn't compatible out of the box. Aside from writing my own little overload for max for the particular form being produced in my line of code from within Eigen, does anyone have a fix for enabling max with expression templates on? MWE: { using mpfr = boost::multiprecision::mpfr_float; // et_on by default, which is what i want using std::max; mpfr a(1), b(2), c(4); auto q = b*b+c; mpfr r = max(a,q); } Thanks a lot, Daniel

1 0

[GIL] Why doesn't pixel assignment color-convert?
by Stonewall Ballard 16 Feb '16

16 Feb '16

I've just started using boost.gil, though I've been looking at it for a while. It seems odd to me that assignment doesn't do an implicit color_convert() when the pixels are of different types. Instead, it just copies matching channels. That's the wrong thing to do when assigning an rgba pixel to an rgb pixel, since the former is straight and the latter is premultiplied. It also seems wrong that you can assign an rgba pixel to an rgb pixel, but not vice-versa. It looks like this is caused by pixels_are_compatible in gil_concept.hpp, where it fails to check that both pixels have the same number of channels. Instead, it matches channels of the output pixel against the input pixel, ignoring any extra input pixel channels. It also ignores scoped_channel_value usage. This seems like an error waiting to happen. Comments? - Stoney

1 0

ASIO: add work and remove immed., will ignore further handler_requests???
by aj neu 16 Feb '16

16 Feb '16

Hi, below is some code where boost::asio::io_service::work is added, and then immediately removed. After that, I call async_wait on a steady_timer, but it does not work: io.run() RETURNS IMMEDIATELY, and IGNORES the async_wait. Is this intended? (I was rather surprised, because I thought that the async_wait would schedule new work, but it does not work). If I cange the code-line #define WEIRD_BEHAVIOUR to #undef WEIRD_BEHAVIOUR then I have my expected behaviour. Thanks, ajneu #include <iostream> #include <chrono> #include <experimental/optional> #include <boost/asio.hpp> #include <boost/asio/steady_timer.hpp> #define WEIRD_BEHAVIOUR int main() { boost::asio::io_service io; std::experimental::optional<boost::asio::io_service::work> work; #ifdef WEIRD_BEHAVIOUR work.emplace(io); work = std::experimental::nullopt; #endif boost::asio::steady_timer timer(io, std::chrono::milliseconds{1000}); timer.async_wait([](const boost::system::error_code &ec) { std::cout << ((!ec) ? "done" : "err") << std::endl; }); io.run(); }

1 0