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I ran b2 with the -d+2 command and redirected the output to a file
by Osman Zakir 05 Jan '19

05 Jan '19

This is a follow-up to the message where I asked for help about a failed attempt to build Boost. I ran b2 with the -d+2 command in addition to the other commands and also redirected the output to a file. It's attached to this message, as well as the project-config.jam file.

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New user : Help on Solaris
by Dechaux Eric CEN (BCQ STIG) 03 Jan '19

03 Jan '19

Hello everyone, I am a Solaris user and need to build pgAgent 4.0 on a Solaris 11.4 X86_64 box. pgAgent require boost withthreading. I have build boost 1.69 with no issue : sol114:/tmp/build/boost_1_69_0$ ./b2 threading=multi -d+2 -a Performing configuration checks - default address-model : 64-bit - default architecture : x86 Building the Boost C++ Libraries. - C++11 mutex : yes - lockfree boost::atomic_flag : yes - Boost.Config Feature Check: cxx11_auto_declarations : yes - Boost.Config Feature Check: cxx11_constexpr : yes - Boost.Config Feature Check: cxx11_defaulted_functions : yes - Boost.Config Feature Check: cxx11_final : yes - Boost.Config Feature Check: cxx11_hdr_mutex : yes - Boost.Config Feature Check: cxx11_hdr_tuple : yes - Boost.Config Feature Check: cxx11_lambdas : yes - Boost.Config Feature Check: cxx11_noexcept : yes - Boost.Config Feature Check: cxx11_nullptr : yes - Boost.Config Feature Check: cxx11_rvalue_references : yes - Boost.Config Feature Check: cxx11_template_aliases : yes - Boost.Config Feature Check: cxx11_thread_local : yes - Boost.Config Feature Check: cxx11_variadic_templates : yes - has_icu builds : yes warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam - zlib : yes - bzip2 : yes - lzma : yes - zstd : no - icu : yes warning: non-free usage requirements <runtime-link>shared ignored warning: in main-target build_options at libs/locale/build/Jamfile.v2:414 warning: non-free usage requirements <runtime-link>shared ignored warning: in main-target build_flags at libs/locale/build/Jamfile.v2:415 - xopen-source-600-supported : yes - native-atomic-int32-supported : yes - native-syslog-supported : yes - pthread-supports-robust-mutexes : yes - compiler-supports-ssse3 : yes - compiler-supports-avx2 : yes - gcc visibility : yes - long double support : yes warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. - libbacktrace builds : no - addr2line builds : yes - WinDbg builds : no - WinDbgCached builds : no - BOOST_COMP_GNUC >= 4.3.0 : no - zlib : yes - bzip2 : yes - lzma : yes - zstd : no Component configuration: - atomic : building - chrono : building - container : building - context : building - contract : building - coroutine : building - date_time : building - exception : building - fiber : building - filesystem : building - graph : building - graph_parallel : building - iostreams : building - locale : building - log : building - math : building - mpi : building - program_options : building - python : building - random : building - regex : building - serialization : building - stacktrace : building - system : building - test : building - thread : building - timer : building - type_erasure : building - wave : building [...] "g++" -fvisibility-inlines-hidden -fPIC -m64 -pthreads -O3 -finline-functions -Wno-inline -w -fvisibility=hidden -DBOOST_ALL_DYN_LINK=1 -DBOOST_ALL_NO_LIB=1 -DNDEBUG -I"." -c -o "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/cpplexer/re2clex/cpp_re.o" "libs/wave/src/cpplexer/re2clex/cpp_re.cpp" gcc.link.dll bin.v2/libs/wave/build/gcc-7.3.0/release/threadapi-pthread/threading-multi/visibility-hidden/libboost_wave.so.1.69.0 "g++" -L"/tmp/build/boost_1_69_0/bin.v2/libs/chrono/build/gcc-7.3.0/release/threading-multi/visibility-hidden" -L"/tmp/build/boost_1_69_0/bin.v2/libs/date_time/build/gcc-7.3.0/release/threading-multi/visibility-hidden" -L"/tmp/build/boost_1_69_0/bin.v2/libs/filesystem/build/gcc-7.3.0/release/threading-multi/visibility-hidden" -L"/tmp/build/boost_1_69_0/bin.v2/libs/system/build/gcc-7.3.0/release/threading-multi/visibility-hidden" -L"/tmp/build/boost_1_69_0/bin.v2/libs/thread/build/gcc-7.3.0/release/threadapi-pthread/threading-multi/visibility-hidden" -o "bin.v2/libs/wave/build/gcc-7.3.0/release/threadapi-pthread/threading-multi/visibility-hidden/libboost_wave.so.1.69.0" -shared "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/instantiate_cpp_exprgrammar.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/instantiate_cpp_grammar.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/instantiate_cpp_literalgrs.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/instantiate_defined_grammar.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/instantiate_predef_macros.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/instantiate_re2c_lexer.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/instantiate_re2c_lexer_str.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/token_ids.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/wave_config_constant.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/cpplexer/re2clex/aq.o" "bin.v2/libs/wave/build/gcc-7.3.0/release/threading-multi/visibility-hidden/cpplexer/re2clex/cpp_re.o" "bin.v2/libs/filesystem/build/gcc-7.3.0/release/threading-multi/visibility-hidden/libboost_filesystem.so.1.69.0" "bin.v2/libs/thread/build/gcc-7.3.0/release/threadapi-pthread/threading-multi/visibility-hidden/libboost_thread.so.1.69.0" "bin.v2/libs/date_time/build/gcc-7.3.0/release/threading-multi/visibility-hidden/libboost_date_time.so.1.69.0" "bin.v2/libs/chrono/build/gcc-7.3.0/release/threading-multi/visibility-hidden/libboost_chrono.so.1.69.0" "bin.v2/libs/system/build/gcc-7.3.0/release/threading-multi/visibility-hidden/libboost_system.so.1.69.0" -lrt -fPIC -m64 -pthreads -fvisibility=hidden -fvisibility-inlines-hidden -mimpure-text common.copy stage/lib/libboost_wave.so.1.69.0 cp "bin.v2/libs/wave/build/gcc-7.3.0/release/threadapi-pthread/threading-multi/visibility-hidden/libboost_wave.so.1.69.0" "stage/lib/libboost_wave.so.1.69.0" ln-UNIX stage/lib/libboost_wave.so ln -f -s 'libboost_wave.so.1.69.0' 'stage/lib/libboost_wave.so' The Boost C++ Libraries were successfully built! The following directory should be added to compiler include paths: /tmp/build/boost_1_69_0 The following directory should be added to linker library paths: /tmp/build/boost_1_69_0/stage/lib However, when I try to build pgAgent 4.0 I have the following errors : sol114:/tmp/build/pgAgent-4.0.0-Source$ make CMake Warning at cmake/FindBoost.cmake:839 (message): New Boost version may have incorrect or missing dependencies and imported targets Call Stack (most recent call first): cmake/FindBoost.cmake:950 (_Boost_COMPONENT_DEPENDENCIES) cmake/FindBoost.cmake:1618 (_Boost_MISSING_DEPENDENCIES) CMakeLists.txt:112 (FIND_PACKAGE) CMake Warning at cmake/FindBoost.cmake:839 (message): New Boost version may have incorrect or missing dependencies and imported targets Call Stack (most recent call first): cmake/FindBoost.cmake:950 (_Boost_COMPONENT_DEPENDENCIES) cmake/FindBoost.cmake:1618 (_Boost_MISSING_DEPENDENCIES) CMakeLists.txt:112 (FIND_PACKAGE) CMake Warning at cmake/FindBoost.cmake:839 (message): New Boost version may have incorrect or missing dependencies and imported targets Call Stack (most recent call first): cmake/FindBoost.cmake:950 (_Boost_COMPONENT_DEPENDENCIES) cmake/FindBoost.cmake:1618 (_Boost_MISSING_DEPENDENCIES) CMakeLists.txt:112 (FIND_PACKAGE) CMake Warning at cmake/FindBoost.cmake:839 (message): New Boost version may have incorrect or missing dependencies and imported targets Call Stack (most recent call first): cmake/FindBoost.cmake:950 (_Boost_COMPONENT_DEPENDENCIES) cmake/FindBoost.cmake:1618 (_Boost_MISSING_DEPENDENCIES) CMakeLists.txt:112 (FIND_PACKAGE) CMake Warning at cmake/FindBoost.cmake:839 (message): New Boost version may have incorrect or missing dependencies and imported targets Call Stack (most recent call first): cmake/FindBoost.cmake:950 (_Boost_COMPONENT_DEPENDENCIES) cmake/FindBoost.cmake:1618 (_Boost_MISSING_DEPENDENCIES) CMakeLists.txt:112 (FIND_PACKAGE) CMake Warning at cmake/FindBoost.cmake:839 (message): New Boost version may have incorrect or missing dependencies and imported targets Call Stack (most recent call first): cmake/FindBoost.cmake:950 (_Boost_COMPONENT_DEPENDENCIES) cmake/FindBoost.cmake:1618 (_Boost_MISSING_DEPENDENCIES) CMakeLists.txt:112 (FIND_PACKAGE) CMake Warning at cmake/FindBoost.cmake:839 (message): New Boost version may have incorrect or missing dependencies and imported targets Call Stack (most recent call first): cmake/FindBoost.cmake:950 (_Boost_COMPONENT_DEPENDENCIES) cmake/FindBoost.cmake:1618 (_Boost_MISSING_DEPENDENCIES) CMakeLists.txt:112 (FIND_PACKAGE) -- Boost version: 1.69.0 -- Found the following Boost libraries: -- filesystem -- regex -- date_time -- thread -- system -- chrono -- atomic -- -- ================================================================================ -- Configuration summary: -- -- Project : pgagent -- Description : pgAgent is a job scheduling engine for PostgreSQL -- Version : 4.0.0 -- -- PostgreSQL version string : PostgreSQL 10.6 -- PostgreSQL version parts : 10 -- PostgreSQL path : /appli/11.4.4.4.0-20181220-10.6 -- PostgreSQL config binary : /appli/11.4.4.4.0-20181220-10.6/bin/pg_config -- PostgreSQL include path : /appli/11.4.4.4.0-20181220-10.6/include -- PostgreSQL library path : /appli/11.4.4.4.0-20181220-10.6/lib -- PostgreSQL share path : /appli/11.4.4.4.0-20181220-10.6/share/postgresql -- -- Boost version : 1.69.0 -- Boost path : /tmp/build/boost_1_69_0 -- Boost include directory : /tmp/build/boost_1_69_0 -- Boost library directory : /tmp/build/boost_1_69_0/stage/lib -- Boost Static linking : NO -- ================================================================================ -- -- Configuring done -- Generating done -- Build files have been written to: /tmp/build/pgAgent-4.0.0-Source [ 11%] Built target run [ 22%] Building CXX object CMakeFiles/pgagent.dir/connection.cpp.o In file included from /tmp/build/boost_1_69_0/boost/thread/detail/platform.hpp:17:0, from /tmp/build/boost_1_69_0/boost/thread/mutex.hpp:12, from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:22, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/config/requires_threads.hpp:47:5: error: #error "Compiler threading support is not turned on. Please set the correct command line options for threading: -pthread (Linux), -pthreads (Solaris) or -mthreads (Mingw32)" # error "Compiler threading support is not turned on. Please set the correct command line options for threading: -pthread (Linux), -pthreads (Solaris) or -mthreads (Mingw32)" ^~~~~ In file included from /tmp/build/boost_1_69_0/boost/thread/mutex.hpp:12:0, from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:22, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/thread/detail/platform.hpp:71:9: error: #error "Sorry, no boost threads are available for this platform." # error "Sorry, no boost threads are available for this platform." ^~~~~ In file included from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:22:0, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/thread/mutex.hpp:18:2: error: #error "Boost threads unavailable on this platform" #error "Boost threads unavailable on this platform" ^~~~~ In file included from /tmp/build/boost_1_69_0/boost/thread/thread.hpp:12:0, from /tmp/build/boost_1_69_0/boost/thread.hpp:13, from /tmp/build/pgAgent-4.0.0-Source/include/job.h:16, from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:37, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/thread/thread_only.hpp:19:2: error: #error "Boost threads unavailable on this platform" #error "Boost threads unavailable on this platform" ^~~~~ In file included from /tmp/build/boost_1_69_0/boost/thread/detail/thread.hpp:21:0, from /tmp/build/boost_1_69_0/boost/thread/thread_only.hpp:22, from /tmp/build/boost_1_69_0/boost/thread/thread.hpp:12, from /tmp/build/boost_1_69_0/boost/thread.hpp:13, from /tmp/build/pgAgent-4.0.0-Source/include/job.h:16, from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:37, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/thread/detail/thread_heap_alloc.hpp:19:2: error: #error "Boost threads unavailable on this platform" #error "Boost threads unavailable on this platform" ^~~~~ In file included from /tmp/build/boost_1_69_0/boost/thread/thread_only.hpp:26:0, from /tmp/build/boost_1_69_0/boost/thread/thread.hpp:12, from /tmp/build/boost_1_69_0/boost/thread.hpp:13, from /tmp/build/pgAgent-4.0.0-Source/include/job.h:16, from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:37, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/thread/condition_variable.hpp:18:2: error: #error "Boost threads unavailable on this platform" #error "Boost threads unavailable on this platform" ^~~~~ In file included from /tmp/build/boost_1_69_0/boost/thread/detail/thread_group.hpp:10:0, from /tmp/build/boost_1_69_0/boost/thread/thread.hpp:13, from /tmp/build/boost_1_69_0/boost/thread.hpp:13, from /tmp/build/pgAgent-4.0.0-Source/include/job.h:16, from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:37, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/thread/shared_mutex.hpp:31:2: error: #error "Boost threads unavailable on this platform" #error "Boost threads unavailable on this platform" ^~~~~ In file included from /tmp/build/boost_1_69_0/boost/thread.hpp:17:0, from /tmp/build/pgAgent-4.0.0-Source/include/job.h:16, from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:37, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/thread/once.hpp:31:2: error: #error "Boost threads unavailable on this platform" #error "Boost threads unavailable on this platform" ^~~~~ In file included from /tmp/build/boost_1_69_0/boost/thread.hpp:18:0, from /tmp/build/pgAgent-4.0.0-Source/include/job.h:16, from /tmp/build/pgAgent-4.0.0-Source/include/pgAgent.h:37, from /tmp/build/pgAgent-4.0.0-Source/connection.cpp:12: /tmp/build/boost_1_69_0/boost/thread/recursive_mutex.hpp:18:2: error: #error "Boost threads unavailable on this platform" #error "Boost threads unavailable on this platform" ^~~~~ I have no idea why the boost headers won't find the availability of threads as it has built fine with pthread : $ ldd /tmp/build/boost_1_69_0/stage/lib/libboost_system.so.1.69.0 libstdc++.so.6 => /usr/lib/64/libstdc++.so.6 libm.so.2 => /lib/64/libm.so.2 librt.so.1 => /lib/64/librt.so.1 libgcc_s.so.1 => /usr/lib/64/libgcc_s.so.1 libpthread.so.1 => /lib/64/libpthread.so.1 libc.so.1 => /lib/64/libc.so.1 Can anybody help me ? Best regards -- Eric Ce message électronique et tous les fichiers attachés qu'il contient sont confidentiels et destinés exclusivement à l'usage de la personne à laquelle ils sont adressés. Si vous avez reçu ce message par erreur, merci de le retourner à son émetteur. La publication, l'usage, la distribution, l'impression ou la copie non autorisée de ce message et des attachements qu'il contient sont strictement interdits. En cas d'urgence, composez le 17 ou le 112. Afin de contribuer au respect de l'environnement, merci de n'imprimer cet e-mail qu'en cas de necessite. This e-mail and any files transmitted with it are confidential and intended solely for the use of the individual to whom it is addressed. If you have received this email in error please send it back to the person that sent it to you. Unauthorized publication, use, dissemination, forwarding, printing or copying of this email and its associated attachments is strictly prohibited. In case of emergency, dial number 17 or 112. To contribute to the environmental protection, please print this e-mail only if necessary.

2 2

ASIO vs Beast DynamicBuffer use
by Cristian Morales Vega 02 Jan '19

02 Jan '19

Hi, I have just noticed that while ASIO passes DynamicBuffers as && (https://www.boost.org/doc/libs/1_68_0/doc/html/boost_asio/reference/async_r…) Beast passes them via reference (https://www.boost.org/doc/libs/1_68_0/libs/beast/doc/html/beast/ref/boost__…) I'm guessing this happens because ASIO thinks you are going to use dynamic_string_buffer/dynamic_vector_buffer as DynamicBuffer, while Beast thinks you are going to use flat_buffer/multi_buffer. In the second case doesn't make sense to give ownership of the DynamicBuffer to the initiation function because then you would not be able to look at the received data when the operation completes. Since ASIO DynamicBuffer implementations are just adaptors over string/vectors that you keep, it makes sense to move those adaptors, you still keep the string/vector with the data. Have I got it right? But this raises the question: what should I use in my own initiating functions? Regards.

2 3

My last message
by Osman Zakir 02 Jan '19

02 Jan '19

Hi, everyone. Did you guys see my last message? I really need to get a reply ASAP.

4 9

function template with a universal reference to a specific type
by Ireneusz Szcześniak 01 Jan '19

01 Jan '19

Hi, I'm writing to ask a C++ question, not specifically Boost-related, but this list is the best place I know. How can I write a function template, which has a parameter of the universal reference to a specific type? I can write a function template like this: template <typename T> void foo(T &&t) { // The primary template implementation. cout << "Primary: " << __PRETTY_FUNCTION__ << endl; } And so I can call this function with an expression of any value category, and any type, cv-qualified or not, like this: int main() { foo(1); int i = 1; foo(i); const int ci = 1; foo(ci); } In my code I need to provide different implementations of foo for different types (and these types are templated). How can I accomplish that? Best, Irek

5 11

Error: no member named 'GetModuleFileNameA' in namespace 'boost::winapi'; did you mean simply 'GetModuleFileNameA'?
by Osman Zakir 31 Dec '18

31 Dec '18

Hi again, everyone. When trying to build Boost 1.69.0 after having placed my installation of Python 3.7.1 above the one of Python 2.7.15, I got the error mentioned in the title of this email. It says at the end, " ...failed updating 4 targets... ...skipped 8 targets... ...updated 2381 targets... " The project-config.jam file I used is attached to this message.

1 0

Errors with 1.69 when compiling with /clr on MSVC
by Stian Zeljko Vrba 30 Dec '18

30 Dec '18

I get the following warning and error when compiling a C++/CLI file that includes boost 1.69. 1>c:\quinesoftwarebase\include\boost\type_traits\detail\is_member_function_pointer_cxx_11.hpp(114): error C2764: 'C': template parameter not used or deducible in partial specialization 'boost::is_member_function_pointer<Ret(Args...)>' 1>c:\quinesoftwarebase\include\boost\type_traits\detail\is_member_function_pointer_cxx_11.hpp(125): warning C4575: '__vectorcall' incompatible with the '/clr' option: converting to '__stdcall' Is there a workaround for this? -- Stian

3 3

Re: [Boost-users] [cfe-dev] [llvm-dev] Error: ISO C++17 does not allow 'register' storage class specifier [-Wregister], when building Boost 1.69.0
by Osman Zakir 25 Dec '18

25 Dec '18

I'll build using C++14 mode, then. I wonder if Python 3.7.1 has this issue as well? If it doesn't, then maybe Boost should switch over to that version of Python. ________________________________ From: Matthieu Brucher <matthieu.brucher(a)gmail.com> Sent: Tuesday, December 25, 2018 2:56 PM To: Oleg Smolsky Cc: Craig Topper; Osman Zakir; clang developer list; cfe-users(a)lists.llvm.org; llvm-dev(a)lists.llvm.org Subject: Re: [cfe-dev] [llvm-dev] Error: ISO C++17 does not allow 'register' storage class specifier [-Wregister], when building Boost 1.69.0 The issue comes in part form the Python headers that have the keyword. Unfortunately, this also means that there is an issue while building user code. But it's not a Boost code issue for this library, but a Python one. Regards, Matthieu Le mar. 25 déc. 2018 à 02:08, Oleg Smolsky via cfe-dev <cfe-dev(a)lists.llvm.org<mailto:cfe-dev@lists.llvm.org>> a écrit : Yes, this keyword is no longer valid starting from C++17: https://en.cppreference.com/w/cpp/keyword/register I realize that the "why" probably doesn't help you move forth with your problem, so here are a couple suggestions how to get over it: * Build Boost in C++14 mode with -std=c++14 * Cut out "register" from the Boost source and rebuild * Try a newer Boost version, it may have been fixed Oleg. On 2018-12-23 09:26, Craig Topper via cfe-dev wrote: This seems a better question for cfe-dev or cfe-users ~Craig On Sat, Dec 22, 2018 at 12:23 PM Osman Zakir via llvm-dev <llvm-dev(a)lists.llvm.org<mailto:llvm-dev@lists.llvm.org>> wrote: When trying to build Boost using LLVM, I had this error: " error: ISO C++17 does not allow 'register' storage class specifier [-Wregister] " I attached the project-config.jam file I used to this message. Someone please help me out (if there's someone on here who can). _______________________________________________ LLVM Developers mailing list llvm-dev(a)lists.llvm.org<mailto:llvm-dev@lists.llvm.org> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev _______________________________________________ cfe-dev mailing list cfe-dev(a)lists.llvm.org<mailto:cfe-dev@lists.llvm.org> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev _______________________________________________ cfe-dev mailing list cfe-dev(a)lists.llvm.org<mailto:cfe-dev@lists.llvm.org> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev -- Quantitative analyst, Ph.D. Blog: http://blog.audio-tk.com/ LinkedIn: http://www.linkedin.com/in/matthieubrucher

2 1

Problem downloading 1.69.0 for Windows
by tim＠raisedbar.net 24 Dec '18

24 Dec '18

Hi, Windows Defender is blocking my download from https://www.boost.org/users/history/version_1_69_0.html as it is identified as being unsafe. Can anybody advise, please? Best wishes. Tim Burgess Raised Bar Ltd. E: <mailto:tim@raisedbar.net> tim(a)raisedbar.net M: +44 (0)7989 486976

2 2

[Asio/Beast] Any non-obvious reasons for no bind_executor_and_allocator?
by Sorin Fetche 23 Dec '18

23 Dec '18

Hi, As I'm looking to modernize an older C++03 project based on Boost.Asio to use C++17 and the net TS api, I am not ready yet to give up on using lambdas for completion handlers. Boost.Asio and Boost.Beast have some utilities for correctly implementing asynchronous composed operations but from them only asio::bind_executor seems to be applicable to lambdas. And the problem is that it only associates an executor with a (lambda) object; I didn't find any utility for associating an allocator too. Could there be any reason for a utility that associates both an executor and an allocator with an object to not work correctly when implementing asynchronous operations? Or is it just that this utility has not been implemented yet? I did come across the paper "Networking TS Associations for Call Wrappers"[1], but I didn't see any mention there about bind_executor or something similar for allocators or why this kind of approach wouldn't work. I would be very happy if I could write something like: asio::post( socket_.get_executor(), bind_executor_and_allocator_from( handler_, [...] { self_.handler_(...); })); and, unless I'm missing something, such a utility could be implemented similarly to the existing asio::bind_executor. Thank you, Sorin [1] http://open-std.org/JTC1/SC22/WG21/docs/papers/2018/p1133r0.html

2 7

Update for C++17 register keyword error question
by Osman Zakir 23 Dec '18

23 Dec '18

This is the error I get when trying to build Boost 1.69.0 with LLVM: "error: ISO C++17 does not allow 'register' storage class specifier [-Wregister]". I've also sent an email about this to the LLVM developer mailing list. I've attached the project-config.jam file to this message. Please let me know how to fix this. Thanks in advance.

2 2

[uuid] constexpr uuid from string and ""_uuid literal
by Tobias Loew 23 Dec '18

23 Dec '18

Hi, while searching for constexpr GUID from string generators, I found https://gist.github.com/AlexBAV/b58e92d7632bae5d6f5947be455f796f . Since I still work with VS 2015, I wrote a C++11 constexpr version incl. boost-uuid generators. If there's interest adding this to boost uuid, please have a look at https://github.com/tobias-loew/constexpr-GUID-cpp-11 Tobias -- Sent from: http://boost.2283326.n4.nabble.com/Boost-Users-f2553780.html

2 1

Patch for using boost-1_69_0 and clang-cl
by JR Cary 23 Dec '18

23 Dec '18

I found that I had to apply the attached patch to build another project that uses boost with clang-cl, or else I got an error that complained about the non-existence of std::snprintf. John Cary

2 1

Error when trying to build Boost 1.69.0 with LLVM
by Osman Zakir 22 Dec '18

22 Dec '18

When trying to build Boost 1.69.0 with LLVM, I had an error about the "register" keyword, regarding the removal of it in C++17. I searched on the Web and found out that I can use the "-Wno-register" flag to calm down Clang 6.0.0. What do I do in Clang 8.0.0? The same?

1 0

boost_1_19_0 fails to build random using clang-cl
by JR Cary 21 Dec '18

21 Dec '18

This is now more of an FYI, as I can disable random and get the build I need. boost 1_69_0 clang version 8.0.0 (trunk 349323) Windows 10 Build command: ./b2 toolset=clang-win runtime-link=shared link=shared define=BOOST_TEST_DYN_LINK cxxflags='-DBOOST_THREAD_DONT_USE_CHRONO' linkflags='-DBOOST_THREAD_DONT_USE_CHRONO' address-model=64 threading=multi variant=release -s NO_COMPRESSION=1 --layout=system --abbreviate-paths -j2 --without-python --without-mpi --without-log --without-math stage The first error is Creating library bin.v2\libs\random\build\clng-win-8.0.0\rls\adrs-mdl-64\thrd-mlt\boost_random.lib and object bin.v2\libs\random\build\clng-win-8.0.0\rls\adrs-mdl-64\thrd-mlt\boost_random.exp^M random_device.obj : error LNK2019: unresolved external symbol __imp_CryptEnumProvidersA referenced in function "public: __cdecl boost::random::random_device::impl::impl(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??0impl@random_device@random@boost@@QEAA@AEBV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z)^M random_device.obj : error LNK2019: unresolved external symbol __imp_CryptAcquireContextA referenced in function "public: __cdecl boost::random::random_device::impl::impl(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??0impl@random_device@random@boost@@QEAA@AEBV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@@Z)^M random_device.obj : error LNK2019: unresolved external symbol __imp_CryptReleaseContext referenced in function "public: __cdecl boost::random::random_device::impl::~impl(void)" (??1impl@random_device@random@boost@@QEAA@XZ)^M random_device.obj : error LNK2019: unresolved external symbol __imp_CryptGenRandom referenced in function "public: unsigned int __cdecl boost::random::random_device::operator()(void)" (??Rrandom_device@random@boost@@QEAAIXZ)^M bin.v2\libs\random\build\clng-win-8.0.0\rls\adrs-mdl-64\thrd-mlt\boost_random.dll : fatal error LNK1120: 4 unresolved externals^M clang-cl: error: linker command failed with exit code 1120 (use -v to see invocation)^M The build succeeds upon adding --without-random to the build invocation. I tried attaching the full log, but then the message was rejected for being too large. ..................John Cary

1 0

Questions about Boost.Multiprecision..
by A Z 20 Dec '18

20 Dec '18

I want to be performing some algebraic functions work on cpp_rational which I will be using templates with the following type to configure precision (and scale?) #include <boost/multiprecision/cpp_int.hpp> in order to avoid the use of floating point types. --What is the #include statement for cpp_rational? I can't manage to find it. -When using non-floating point, is there a method to obtain a variable precision pi, or do I have to use arccos(-1); ? What is the file to import for that? -If I want to import a non-floating-point (cpp_rational) library power, nth root, trigonometry, all the useful function, what is the #include and the file in boost for that?

2 1

Having some trouble with bootstrapping Boost to use LLVM
by Osman Zakir 20 Dec '18

20 Dec '18

I changed the project-config.jam file in my Boost source tree to have Boost.Build use LLVM, but then when I used "bootstrap" command after, I saw that it was still using MSVC. When I looked at the project-config.jam file again at that point, I saw that its content had been reverted back to the default one for building with MSVC. What's going on? What do I need to do? Is there an argument I need to provide to the bootstrap command here so that it'll keep the configuration file content that I want it to? And is there no help command that would let me see what arguments, if any, I can pass to the tool? Another thing I want to ask is whether or not I need to have Boost.Built emit library files with a .bc extension to be able to link them with code I want to build using the Emscripten compiler. I ask because Emscripten needs compiled libraries to have been compiled to LLVM bitcode, and when Emscripten itself does this it adds the .bc extension instead of the .lib one.

2 2

integer_log2.hpp header deprecation using Boost
by Michael Powell 19 Dec '18

19 Dec '18

Hello, I am receiving a deprecation warning: d:\dev\boost.org\boost_1_69_0\boost\pending\integer_log2.hpp(7): note: This header is deprecated. Use <boost/integer/integer_log2.hpp> instead. The immediate includes are these: #include <boost/uuid/uuid.hpp> #include <boost/uuid/uuid_io.hpp> #include <boost/uuid/random_generator.hpp> But I am also leveraging Spirit, Format, Variant, Optional, to name a few, that I can determine. I am not including "integer_log2.hpp" directly, so I wondered which library(ies) might have this as a dependency? Spirit? Phoenix, via Spirit? Format? Thoughts? Suggestions? Cheers, Michael Powell

1 1

odeint: how to solve ODE as you go without deciding upfront what the interval is?
by Yuri 19 Dec '18

19 Dec '18

The function 'integrate' solves ODE for a pre-defined interval of time. What if I don't know what the interval is? I just need a few values, and then I would like to decide if I need more values, and when to stop. I don't want to just solve for some arbitrarily large interval, because this would waste CPU. On the other hand, choosing the shorter original interval and then continuing would introduce unnecessary errors if one would do this too many times. It seems like either the 'observer' function should have another argument: 'stop', or the interface should allow continuation. Yuri

1 0

[Spirit] X3 thread-safety
by Igor R 19 Dec '18

19 Dec '18

Hello, In my project I run x3-based parsers in parallel, using openmp. I've just moved from boost 1.64 to 1.68, and the parsers now cause segfault (heap corruption) - quite consistently, every time I run the program. OTOH, with 1.64 it never crashed. Before I begin to debug it in depth, I'd like to know if there's some known issue with Spirit's thread-safety in Boost 1.68. Did anyone encounter thread-safety issie with the recent Spirit versions? Thanks.

1 0

Build boost asio http server examples single threaded using c++03
by Eric Curtin 19 Dec '18

19 Dec '18

Hi Guys, I was wondering if anyone could help me out building all the boost asio http server examples from: https://github.com/boostorg/asio/tree/develop/example/cpp03/http But catch is, I need to use c++03/98, single threaded without dependencies on std::thread, boost::thread or posix threads. I also need static linking to all the other boost libraries. Also want to compile with g++ -O3 -flto on x86_64 Linux. How can I build these examples like this? This is also a question on stackoverflow: https://stackoverflow.com/questions/53822438/building-boost-asio-without-th… Lets say the build environment is this one: curtine/dockerfiles-fat:ubuntu18.04 Regards, Eric

2 1

[Asio] Combining use_future with strands
by Sorin Fetche 19 Dec '18

19 Dec '18

Hi, Is there a way to combine the special use_future completion token with a strand? Something with the meaning of: - the asynchronous operation should pass the result to the future it returns, and - the internal operations of it (if any) should run in a strand Code snippet: asio::io_context io_context; asio::io_context::strand strand(io_context); std::future<void> f = async_my_operation(io_context, <params>, asio::use_future); //________________________________________How to add the strand here ^^^ ? The code area where I would like to apply this is in this test program: https://github.com/sorf/cpp-dev-new/blob/abf9d831a0b82fb81751eee6cfa498d3b9… The self contained program and its output is here: https://wandbox.org/permlink/pF5Hbm6jqPOmEKbO As a background, the test program I wrote is based on these Boost.Asio examples: - for strand usage (i.e. bind_executor): https://github.com/boostorg/asio/blob/develop/example/cpp03/tutorial/timer5… - for composed operations: https://github.com/boostorg/asio/blob/develop/example/cpp11/operations/comp… and implements a composed operation that runs multiple internal operations in parallel and in series. Similar to the constructor of a socket or a timer object, the operation receives as a parameter an io_context; it doesn't offer an overload that receives a strand object directly. The operation is then tested with callback completion, callback completion in a strand, future and future + strand (where the test fails). Thank you, Sorin

5 7

How to implement a visitor pattern over an AST
by Michael Powell 19 Dec '18

19 Dec '18

Hello, I have an AST successfully building, generating text file, and subsequently Spirit Qi parsing for verification purposes. Now I want to implement a visitor pattern over that AST, somehow... For "calculators" and such, "evaluating" those expressions is one thing; however, this AST is not that. It is closer akin to a parsed Xml or Json model/tree. In other words, I'd like for it to feel sort of like an iterator if that's even possible. It should have contextual awareness where it is at all times, etc, perhaps "incrementing" is a depth first analysis. In particular I have in mind to iterate the expected and actual AST results in order to perform the verification. In other words, I might do something like this: auto expected_it = ast_visitor{&expected}; auto actual_it = ast_visitor{&actual}; REQUIRE(expected_it); REQUIRE(actual_it); REQUIRE(*expected_it == *actual_it); // Rinse and repeat ++expected_it; ++actual_it; REQUIRE(*expected_it == *actual_it); I wonder if something like this is even possible from the Boost libraries? Or interested to hear any insights on the subject. For that matter, I wonder it is more appropriate to simply implement the logical operators. Thanks! Michael Powell

4 7

Understanding fibers
by Stephan Menzel 18 Dec '18

18 Dec '18

Hello @ll, I am in the process of transforming a sync server application to an async approach. The framework in use (not asio) instantiates and calls an object representing the call when a request comes in, allows me to do things, fill a response object and then expects me to call a finish() method which will send the response and start the next request. This is not what this question is about but more like my circumstances. All code is pseudocode please... void rpc_work() { const value = do_stuff(request); response.fill_value(value) parent->finish(); } Now some of the calls will imply calling methods, which block on some operations, waiting for external resources to respond. Obviously in an async server with only one thread, this will block everything. So I'm looking for a clever way to structure this. My approach so far (in the prototype) is to go boost::async() for those operations. Like this: void rpc_work() { // prepare work boost::async(launch::any, [request, response, parent]() { const value = do_blocking_stuff(request); response.fill_value(value) parent->finish(); }); } The way I understand boost::async or indeed std::async is, that normally it will just spawn a thread for the operation. The best I can hope for is a thread pool but this is not guaranteed either (on Linux x64 gcc 7.3). So I started looking into fibers but I'm having a hard time understanding them, which is why I post here. From what I gather, what I have here is a prime use case as it matches many things the docs talk about. And yet they also suggest that the fibers are very intrusive and everything underneath do_blocking_stuff() would have to be aware of being in a fiber and yield() when appropriate. Is this correct? What would this mean? Most if not all of the blocking operations are using boost::thread::futures in their blocking things. They would do things like... value_t do_blocking_stuff(request) { boost::future<value_t> fv = retrieve_value_from_somewhere(); fv.wait_for(timeout); return fv.get() } Now, considering I would use fibers in the server, would I have to use 'fiber futures' here to make this work? To make the blocking functions automatically 'fiber aware' and yield() when they would block? This would imply replacing the thread::futures? And if so, how will I know when the value is there and they are ready to continue? And how will I cause this continuation? Do I have to keep track of them and somehow poll() them in a loop or something? I am aware of the broad nature of my question but perhaps someone can chime in and give some hints that allow me to understand them better. They look like they would fit my use case perfectly but I am a bit reluctant of dragging the concept all throughout the code until I realize it won't work. Perhaps someone can eli5 this to me ;-) Cheers, Stephan

4 13

Boost Process fails on Solaris 10 in async mode
by Sanket Sharma 18 Dec '18

18 Dec '18

Hi, I tried installing boost process on my Solaris 10 Sparc machine. On compiling it using gcc-6.3.0, I ran into a static assert failure at compile time at https://github.com/boostorg/process/blob/boost-1.68.0/include/boost/process…. In order to fix that, I changed static_assert(!WIFEXITED(still_active) && !WIFSIGNALED(still_active), "Internal Error"); to static_assert(!WIFEXITED(still_active), "Internal Error"); There is some discussion about this at https://www.openwall.com/lists/musl/2018/08/10/1 Now, the following code works well onCentOS 7(where no change was made to Boost process), but fails on Solaris 10 (where I made the above change as a workaround). On Solaris 10, the return code is 127 and stdout and stderr are empty. #include <iostream>#include <thread>#include <boost/process.hpp>#include <boost/asio.hpp> namespace bp = boost::process ;int main(int argc, char** argv){ std::future<std::string> dataOut; std::future<std::string> dataErr; std::string command = "ls"; boost::asio::io_service ios; bp::child c(command, bp::std_out > dataOut, bp::std_err > dataErr, ios); ios.run(); c.wait(); int result = c.exit_code(); std::string stdOut = dataOut.get(); std::string stdErr = dataErr.get(); std::cout << "Exit Code " << result << std::endl; std::cout << "stdOut " << stdOut << std::endl; std::cout << "stdErr " << stdErr << std::endl; return 0;} Output on CentOS 7 Exit Code 0 stdOut a.out main.cppProcess.cppProcess.h simple.cpp stdErr Output on Solaris 10 Exit Code 127 stdOut stdErr 1. Has my workaround to install Boost process on Solaris 10 broken it? 2. Is Boost-1.68.0 not supported on Solaris? 3. Is there a way I can get Boost Process to work on Solaris 10 in async mode? https://stackoverflow.com/questions/53780273/boost-process-fails-on-solaris… -- Regards, Sanket

1 0

Boost version 1.69.0 already included in list of known versions in FindBoost.cmake module
by Osman Zakir 17 Dec '18

17 Dec '18

I looked in the FindBoost.cmake module and saw that version 1.69.0 is already listed as a known version. But when I configured CMake to build Jinja2Cpp after building Boost 1.69.0, I couldn't get it to find some modules of Boost. There were warning messages about imported targets and dependences or some such. Jinja2Cpp uses an earlier version of Boost from its own submodule in this case (it has a GitHub repository that I cloned from and built), but I'd like it if it used the latest version of Boost instead of an earlier version. My Boost installation is in C:/boost_1_69_0/, by the way. Could this be causing problems, or will it still be fine I configure CMake correctly? What CMake option should I use to find Boost? -DBOOST_ROOT?

3 5

[Spirit] Comment skipper or first class member of grammar
by Michael Powell 17 Dec '18

17 Dec '18

Hello, I am turning a corner in my Protocol Buffers grammar, and it is now time for me to consider how best to approach parsing comments. Chiefly, I am weighing two options, I think: 1) A white-space, comments skipper; if memory serves there has been discussion about such a thing on either here, Boost mailing list, or other forums. 2) Or, as with some compiler environments, I'm thinking .NET Roslyn/C#, in particular, where "comment" elements are first class members of the grammar/tokens, quite literally, I think. I'm not quite sure how that would be expressed in terms of synthesized AST, when you could literally have a comment appearing virtually anywhere between tokens, especially of the C variety, i.e. /* this is a comment which may appear virtually anywhere between tokens, potentially */. Or the single line C++ variety, for example, // this is a comment through the rest of this line. // Yet, there could be multiple lines of these... optional myVar = true; // And can appear at the end of a line Thoughts? Suggestions? My first approach I think would be for (1) the skipper; however, for what I am wanting to accomplish, I can see there potentially being some value in capturing the comments and carrying them forward with the target language adapter. Best regards, Michael Powell

1 1

[process] distinguish normal exit from termination by signal - complete
by Oliver Kowalke 17 Dec '18

17 Dec '18

Hello, I'm evaluating boost.process. It seams to me that it is impossible to distinguish a normal exit from a termination by a signal (for instance SIGBUS etc.). child::exit_code() calls eval_exit_status() that expands on POSIX to: if (WIFEXITED(code)) { return WEXITSTATUS(code); } else if (WIFSIGNALED(code)) { return WTERMSIG(code); } else { return code; } With the code above it is impossible if the returned exit_code is a `exit-code` or the number of a signal. Or do I miss something? regards, Oliver

1 0

[process]distinguish normal exit from signaled not possible?
by Oliver Kowalke 17 Dec '18

17 Dec '18

Hello, I'm evaluating boost.process. It seams to me that it is impossible to distinguish a normal exit from a termination by a signal (for instance SIGBUS etc.). child::exit_code() calls eval_exit_status() that expands on POSIX to: if (WIFEXITED(code)) { return WEXITSTATUS(code); } else if (WIFSIGNALED(code)) { return WTERMSIG(code); } else { return code; }

1 0

[contextual async] generator support added
by Christophe Bailly 16 Dec '18

16 Dec '18

Hello, I am still waiting for some feedbacks. I really think it makes possible to add asynchronous code very easiy, I have added the support of generators which can run with asynchronous.code. You will find the added article in the blog: https://pythonc.home.blog/ The project has been updated and the examples are available if you want to test. Regards, Chris

2 2

[corountine2/context] forced_unwind exception on Windows with TDM-GCC
by Hao Jiang 15 Dec '18

15 Dec '18

Hello all, I am porting my program from Linux to Windows with boost coroutine2. I found 32bit program throwing boost::context::detail::forced_unwind every time when coroutine destructed. But 64bit program works like charm. terminate called after throwing an instance of 'boost::context::detail::forced_unwind' The program works well on Linux(Ubuntu). Then I tried the official example: typedef boost::coroutines2::coroutine<int> coro_t; coro_t::pull_type source( [&](coro_t::push_type& sink){ int first=1,second=1; sink(first); sink(second); for(int i=0;i<8;++i){ int third=first+second; first=second; second=third; sink(third); } }); for(auto i:source) std::cout << i << " "; Same thing happened. Platform: windows 7 64 bit Boost: 1.67/1.69 Compiler: TDM-GCC 5.1 64bit. Best,

3 4

project-config.jam File for building Boost with LLVM toolchain?
by Osman Zakir 15 Dec '18

15 Dec '18

Sorry, but I need to see the project-config.jam file I need to use for building Boost with the LLVM toolchain again. I'm going to build it with the MSVC toolchain first and then again with the LLVM toolchain as well so that I have both the MSVC- and Clang-generated binaries. I downloaded Boost version 1.69.0 and I want to build it now. Thanks in advance.

5 11

[boost] mixing async + sync code easily via boost::context
by Christophe Bailly 15 Dec '18

15 Dec '18

Hello, I have worked on a prototype to avoid the current limitations with async code, the use of sync + async code is really difficult, it does not co-exist easily. If you introduce async code, you have to migrate all your code ... There are alternative solutions (threads..) but here is a suggestion to overcome these limitations. It is currently a very simple prototype but I would be interested to have your feedback. I think this kind of solution can be really powerfull, but I will wait to know what you think about it. Here are the links: https://pythonc.home.blog/ https://github.com/chbailly/5a5 Regards, Chris

1 0

C++Now (BoostCon) 2019 Call for Submissions
by Jon Kalb 14 Dec '18

14 Dec '18

The C++Now (formerly BoostCon) 2019 Call for Submissions is now open. http://cppnow.org/announcements/2018/12/2019-call-for-submissions/ C++Now will be held in Aspen, Colorado on May 5th - 10th. Colorado has become trendy for C++ conferences, but BoostCon was here first. If you are interested in Boost Libraries and have never attended C++Now, you owe it to yourself to have the BoostCon experience. The best way to get your company to send you is to have an accepted submission. The deadline is early in the new year, so don’t delay. Jon Kalb Conference Chair C++Now

1 0

[release] Boost 1.69.0
by Marshall Clow 13 Dec '18

13 Dec '18

Release 1.69.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains numerous enhancements and bug fixes for existing libraries. For details, including download links, see < http://www.boost.org/users/news/version_1.69.0> You can also download directly from: < https://dl.bintray.com/boostorg/release/1.69.0/> SHA-256 sums: af05616f71006f97833e130aad886c96136457511ace4b5496d6566e69cbe0ca boost_1_69_0.7z 8f32d4617390d1c2d16f26a27ab60d97807b35440d45891fa340fc2648b04406 boost_1_69_0.tar.bz2 9a2c2819310839ea373f42d69e733c339b4e9a19deab6bfec448281554aa4dbb boost_1_69_0.tar.gz d074bcbcc0501c4917b965fc890e303ee70d8b01ff5712bae4a6c54f2b6b4e52 boost_1_69_0.zip To install this release on your system, see < http://www.boost.org/doc/libs/release/more/getting_started/index.html> Thanks to everyone who participated in this release. Thanks, -- The Boost Release Team Vladimir Prus, Marshall Clow, Daniel James, Micheal Caisse

3 2

The Master branch is still closed; it will be opened tomorrow
by Marshall Clow 12 Dec '18

12 Dec '18

Thanks for your patience -- The boost release managers

1 0

Formatting Boost.Uuid as string
by Michael Powell 11 Dec '18

11 Dec '18

Hello, I see that you can do "basic" formatting of boost::uuids::uuid via boost::format. This is good for basic formatting, but are there other format specifiers one can furnish? I'm thinking along the lines of formats such as with or without hyphens, etc. Or an ability to extend such a feature for that matter. See my C# WPF GuidGen for some examples: http://github.com/mwpowellhtx/guidgenwpf/tree/master/src/GuidGen.Wpf/Formats This is based on the Microsoft GuidGen, but using WPF technology, and with some additional formats. Thanks! Best regards, Michael Powell

1 0

[release] 1.69.0 closed for release
by Marshall Clow 11 Dec '18

11 Dec '18

The master branch is now closed for all changes except by permission. The commit-bot isn't running on master, so the super project will need to be manually updated for any changes. If all goes well, the release candidate should be out later today. Thanks, -- The Boost Release Team

3 4

travis runners version
by Alain Miniussi 10 Dec '18

10 Dec '18

Hi, I see that travis runners uses open MPI 1.6.5 mpirun.openmpi --version mpirun.openmpi (OpenRTE) 1.6.5 which is considered "retired" on the OpenMPI download page (https://www.open-mpi.org/) current version is 4.0.0 and most linux ditrib I see uses 2.x.x or hirgher. What is the travis runners distrib/version ? Thanks -- ----- Alain Miniussi DSI, Pôles Calcul et Genie Log. Tél. : +33492003009 (Mont-Gros) Tél. : +33483618544 (Sophia Antipolis)

1 0

Boost.Filesystem perms on Windows
by Lars 10 Dec '18

10 Dec '18

Hello, The documentation<https://www.boost.org/doc/libs/1_68_0/libs/filesystem/doc/reference.html#En…> (boost version 1.68) for boost::filesystem::perms enumerator says; "Windows: All permissions except write are currently ignored. There is only a single write permission; setting write permission for owner, group, or others sets write permission for all, and removing write permission for owner, group, or others removes write permission for all." Does "All permissions except write are currently ignored" restriction apply to both getting permission from a file and setting permission to a file? In other words, does it apply to both boost::filesystem::status(..) and boost::filesystem::permissions(..) methods? Why does the fileysystem have this restriction? Is this some limitation in the design or a bug or missing feature? Kind regards, Lars

2 3

Mocking with boost.test
by Sean Farrow 09 Dec '18

09 Dec '18

Hi all, I was just wondering whether boost.test provides any mocking facilities? If it doesn't is there a recommended mocking framework? Any help appreciated. Kind regards Sean.

4 3

GIL: New file io, almost there, but can't compile 'write_view'
by Dan Bloomquist 08 Dec '18

08 Dec '18

So, I had to deal with a lib I worked on last a couple of years ago. Great news, the file IO has been greatly simplified in 1.68. I was able to retire several dozens of cryptic,(for me), lines. The old code won't compile as the Adobe extensions are gone. I'm almost there, I can read files, but I don't understand why I can't get the writer to compile. I get to my code, in case it matters: bg::rgb8_image_t destImg( res, x ); resize_view( view( sourceImg ), view( destImg ), bg::bilinear_sampler( ) ); and rgb8_image_t should be a good one from what I read: <https://www.boost.org/doc/libs/1_68_0/libs/gil/doc/html/io.html> With either: bg::write_view( path_to, destImg, bg::jpeg_tag() ); or: bg::image_write_info<bg::jpeg_tag> write_setttings; bg::write_view( path_to, destImg, write_setttings ); ms140 complains: 1>C:\cpp\boost_1_68_0\boost/gil/extension/toolbox/metafunctions/get_pixel_type.hpp(33): error C2039: 'reference': is not a member of 'boost::gil::image<boost::gil::rgb8_pixel_t,false,std::allocator<unsigned char>>' 1> c:\cpp\boost_1_68_0\boost\gil\typedefs.hpp(176): note: see declaration of 'boost::gil::image<boost::gil::rgb8_pixel_t,false,std::allocator<unsigned char>>' 1> console_test.cpp(248): note: see reference to class template instantiation 'boost::gil::get_pixel_type<boost::gil::rgb8_image_t>' being compiled 1>C:\cpp\boost_1_68_0\boost/gil/extension/toolbox/metafunctions/get_pixel_type.hpp(34): error C2146: syntax error: missing '>' before identifier 'reference' What am I missing? Do I need to supply more information? I'll put the whole thing in a url if needed. Thanks, Dan.

2 3

[release] Boost 1.69.0 Release Candidate 1
by Marshall Clow 07 Dec '18

07 Dec '18

The release candidates for the 1.68.0 release are now available at: <https://dl.bintray.com/boostorg/release/1.69.0/source/> The SHA256 checksums are as follows: af05616f71006f97833e130aad886c96136457511ace4b5496d6566e69cbe0ca boost_1_69_0_rc1.7z 8f32d4617390d1c2d16f26a27ab60d97807b35440d45891fa340fc2648b04406 boost_1_69_0_rc1.tar.bz2 9a2c2819310839ea373f42d69e733c339b4e9a19deab6bfec448281554aa4dbb boost_1_69_0_rc1.tar.gz d074bcbcc0501c4917b965fc890e303ee70d8b01ff5712bae4a6c54f2b6b4e52 boost_1_69_0_rc1.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Boost Release Managers

2 2

error_code using c++11 and boost
by Lars 07 Dec '18

07 Dec '18

Hello, A project that uses Boost 1.6X (filesystem, uuid, asio) and C++14 on multiplatform. Does it make sense to use std::error_code in this project ? The concern is compatibility between boost and std. The filesystem_error exception will return a boost ::system::error_code which is not compatible with std::error_code as far as I can tell. Exception is not an option. Would it be possible for boost to implement some sort of convertion method from boost::system::error_code to std::errror_code? Thanks kind regards, Lars

3 2

Re: [Boost-users] error_code using c++11 and boost
by Bjorn Reese 06 Dec '18

06 Dec '18

On 11/16/18 4:06 PM, Lars via Boost-users wrote: > Would it be possible for boost to implement some sort of convertion > method from boost::system::error_code to std::errror_code? The upcoming 1.69 release of Boost.System has built-in support for std::error_code. If you need to use earlier versions, then you can create a bridge between the two: http://breese.github.io/2016/06/18/unifying-error-codes.html

3 2

[Spirit] How to prohibit reserved names from matching
by Michael Powell 06 Dec '18

06 Dec '18

Hello, Let's say I have some Qi rules: qi::rule<It, char()> mych; qi::rule<It, std::string()> myname; struct reserved_names_t : qi::symbols<path_t, path_t> { reserved_names_t() { this->add("CON", "CON") ("PRN", "PRN") ("AUX", "AUX") ("NUL", "NUL") ("COM1", "COM1") ("COM2", "COM2") ("COM3", "COM3") ("COM4", "COM4") ("COM5", "COM5") ("COM6", "COM6") ("COM7", "COM7") ("COM8", "COM8") ("COM9", "COM9") ("LPT1", "LPT1") ("LPT2", "LPT2") ("LPT3", "LPT3") ("LPT4", "LPT4") ("LPT5", "LPT5") ("LPT6", "LPT6") ("LPT7", "LPT7") ("LPT8", "LPT8") ("LPT9", "LPT9") ; } } reserved_names; Assuming I've defined mych accordingly, the simple approach would be: myname %= +myname; This gets me the name in the character set. Now, I want to prohibit the reserved names from matching. myname %= ~qi::no_case[reserved_names] | +myname; However, this does not seem to work. I suppose it is one thing ruling out invalid characters, but what about prohibiting whole strings? Thanks in advance for any insights... Michael Powell

1 0

LLVM bitcode for Boost libraries?
by Osman Zakir 06 Dec '18

06 Dec '18

I want to build a project I have, which has to link against Boost.System, to WebAssembly, and it seems like I have to generate LLVM bitcode for it first. Is it possible to use the bootstrapper that comes with the Boost distribution to do this on Windows 10? The project in question is on GitHub here: https://github.com/DragonOsman/currency_converter . I switched out the Asio in the Boost distribution with the official Emscripten port of Asio, found here: https://github.com/emscripten-ports/asio . But I don't know which version of Boost.Asio it's using so I'd like some clarification on that if possible (I opened this issue there: https://github.com/emscripten-ports/asio/issues/2 and have just now updated the question to ask what version of Asio is being used for the port). [https://avatars0.githubusercontent.com/u/18173932?s=400&v=4]<https://github.com/emscripten-ports/asio/issues/2> Update of Asio port? · Issue #2 · emscripten-ports/asio<https://github.com/emscripten-ports/asio/issues/2> Sorry if this is an unwelcome question, but I want to ask if there'll ever be an update to this port of Asio to Emscripten/WebAssembly. I notice it's from 2015. Which version of Boost is it... github.com [https://avatars1.githubusercontent.com/u/8116924?s=400&v=4]<https://github.com/emscripten-ports/asio> GitHub - emscripten-ports/asio<https://github.com/emscripten-ports/asio> Join GitHub today. GitHub is home to over 28 million developers working together to host and review code, manage projects, and build software together. github.com [https://avatars0.githubusercontent.com/u/18173932?s=400&v=4]<https://github.com/DragonOsman/currency_converter> GitHub - DragonOsman/currency_converter: Application for Computer Science course<https://github.com/DragonOsman/currency_converter> Google Maps + Currency Converter Web Application. Application for Computer Science course. This is a currency converter web application with the frontend and a backend. github.com

5 14

Boost.Beast vs Boost.Asio
by Cristian Morales Vega 04 Dec '18

04 Dec '18

There are lots of things which I would expect to be in Boost.Asio which are actually in Boost.Beast. Why? Most of it is "helping" code/docs. For example: - Documentation about (and public interfaces to simplify) the creation of composed operations https://www.boost.org/doc/libs/develop/libs/beast/doc/html/beast/using_io/w… - beast::buffers_cat - beast::test::stream (to be fair, it's in experimental) But now we even have code to work around issues in Boost.Asio which ideally would simply be fixed in Boost.Asio. For example: beast::ssl_stream. I'm personally using all of the above, they are extremely useful. I just supposed it is because there is only one person working on Boost.Asio, and Christopher must be quite busy with life and getting Networking TS into the standard. I was hoping all this would go away by 2020 and I was ignoring the issue. But since now it seems Networking TS will have to wait for 2023... well, I am asking myself how to handle an increasing amount of references to Beast that in a future could change to Asio (potentially with slightly different names/semantics). So I am writing this hoping for some light on the situation.

5 10

Re: [Boost-users] [asio] UDP recv error handling
by Bjorn Reese 03 Dec '18

03 Dec '18

On 11/22/18 3:44 PM, Klebsch, Mario via Boost-users wrote: > Are there any recommendations on how to decide, whether the receive > callback function should re-initiate a receive operation after a receive > error or not? Unlike TCP, UDP does not establish a connection. By default you will not receive any network errors on a UDP socket. You have to call connect() on the socket in order to receive (ICMP) error messages, but this has other implications. With UDP it is more common to rely on application layer error messages and/or timeouts.

2 1

Monitor OSX kqueue descriptor for events with ASIO
by Blaine Walls 02 Dec '18

02 Dec '18

Hi all, I'm using boost::asio on OS X. I'd like to watch for changes to a particular regular file - per Apple's documentation, the preferred method for this is with the kevent API. So I do the following: 1) Wrap a kqueue file descriptor (obtained via a call to kqueue()) in a boost::asio::posix::stream_descriptor with boost::asio::posix::stream_descriptor::assign(). 2) Call boost::asio::posix::stream_descriptor::async_wait() to be notified of file events. The problem appears to be that boost::asio::posix::stream_descriptor::async_wait() uses ioctl() w/ FIONBIO to put the file into non-blocking mode, which fails with "Inappropriate ioctl for device". A normal blocking call to wait() works just fine. I realize that my problem is that the kqueue descriptor does not represent a stream of bytes, so it's probably invalid to use stream_descriptor to wrap it. Does anyone have any ideas on how to work around this? I looked for a type concept for a non-stream descriptor that I could implement, but I didn't see anything obvious. Thanks in advance for any advice, -Blaine

1 0

boost/units - converting forces (lbf->N)
by Matt Vinson 01 Dec '18

01 Dec '18

To see if I understand the library, I want to create metric and imperial systems without using Boost Units predefined systems*. Conversions between lengths are going well. Conversion between forces are going well until pounds-force to newtons; line 182 in the link. What am I doing wrong when lbf will not convert to newtons? Here is my code: https://coliru.stacked-crooked.com/a/f5f80d39fbdf8013 Any help is appreciated. * //imperial namespace boost {namespace units { namespace us {}}}//sinamespace boost { namespace units { namespace si {}}}

3 4

Boost on Android-ndk
by Philip_liu 30 Nov '18

30 Nov '18

Hi everyone, I want to build a boost on android-ndk in ubuntu18.04,I had tried boost 1.58 and 1.68 on android-ndk r10e r13b r15c,and all failed at the step "./b2 \"with error"version 'xx' of default 'g++' does not match".Hope to know how to solve the problem or tell me how to install successfully with the right version in ubuntu18.04. Best Regard, Philip Liu

2 1

[Spirit] Qi Symbols mapping to AST enum
by Michael Powell 28 Nov '18

28 Nov '18

Hello, I've got a qi::symbols capturing some built-in types. At the moment, I gather, they are mapped to std::string. However, I would rather map them to an AST level enum. For instance, struct builtin_type_t : qi::symbols<char, std::string> { builtin_type_t() { this->add("double", "double") ("float", "float") // ... ; } } builtin_type; Instead, namespace ast { enum type_t { type_double, type_float /* , ... */ }; } struct builtin_type_t : qi::symbols<char, ast::type_t> { builtin_type_t() { this->add("double", ast::type_double) ("float", ast::type_float) // ... ; } } builtin_type; I assume this is possible? Am I missing something about that? Thanks! Michael Powell

2 1

Boost intrusive list volatile hook
by nat ersoz 26 Nov '18

26 Nov '18

I intend to use the boost intrusive list to implement an observer pattern. - The list will cross interrupt boundaries; meaning one interrupt will produce the notifications and the other interrupt will observer the notifications. - The observer, in response to a notification, might detach itself from the list using the the hook's unlink() function. - I think that I will need the hook to be declared volatile in order to accommodate this. I have a minimal code sample here: https://github.com/natersoz/patterns/blob/master/observer/intrusive_list_me… My list hook member declaration: using list_hook_type = boost::intrusive::list_member_hook< boost::intrusive::link_mode<boost::intrusive::auto_unlink> >; list_hook_type hook; My list declaration: using list_type = boost::intrusive::list< Observer<NotificationType>, boost::intrusive::constant_time_size<false>, boost::intrusive::member_hook< Observer<NotificationType>, typename Observer<NotificationType>::list_hook_type, &Observer<NotificationType>::hook> >; If I a the volatile keyword to the list hood type, I cannot figure out how to get the list_type declaration to fit into the list template list. Is it possible? Thank you. -- Nat Ersoz 425-417-5182 (cell)

3 3

Re: [Boost-users] Interprocess: limited boost::any in shared memory
by Ferguson, Neil D CTR (US) 26 Nov '18

26 Nov '18

Mr. de Vries, std::variant looks like it should work splendidly. boost::variant might be even better. Thank you. BTW: this is my first user group interaction; I hope I am responding correctly. Neil Ferguson -----Original Message----- From: Maarten de Vries [mailto:maarten@de-vri.es] Sent: Wednesday, November 21, 2018 1:06 PM To: boost-users(a)lists.boost.org Cc: Ferguson, Neil D CTR (US) <neil.d.ferguson.ctr(a)mail.mil> Subject: [Non-DoD Source] Re: [Boost-users] Interprocess: limited boost::any in shared memory All active links contained in this email were disabled. Please verify the identity of the sender, and confirm the authenticity of all links contained within the message prior to copying and pasting the address to a Web browser. ________________________________ On Wed, 21 Nov 2018 at 20:58, Ferguson, Neil D CTR (US) via Boost-users <boost-users(a)lists.boost.org < Caution-mailto:boost-users@lists.boost.org > > wrote: Sirs and madams, I hope to use boost interprocess shared memory to pass complex and dynamic data structures between processes on a host efficiently. The structures will be comprised only of simple primitives (int, float, etc.), interprocess basic_string, interprocess containers (vectors and maps), containers of containers, and (possible deal killer) boost::any. From the interprocess documentation, it _looks_ like the preceding is doable, aside from boost::any. The boost::any objects will themselves contain only primitives, basic_string, or interprocess vectors of unsigned char. So it _looks_ like the data held by the any should be okay. My question: does boost::any use pointers, references, or other constructs that preclude the class from working in shared memory? Thanks for your advice. Neil Ferguson Take a look at /usr/include/boost/any.hpp . You will see that the actual content of the any object is a pointer created with `new` and cleaned up with `delete`. So this will not work properly in shared memory. You could consider using std::variant instead, which does not put storage on the heap (unless contained objects do it themselves, of course). Kind regards, Maarten de Vries

2 1

IOStream: Determine number of bytes written to array sink
by Peter Klotz 23 Nov '18

23 Nov '18

Hello The program below decompresses a std::string using Boost.IOStream. The target is an array sink of fixed size. The users know the decompressed size in advance but for security reasons I need to check the number of bytes written to the sink. If the array is too small, a "write area exhausted" exception is thrown, which is fine. If the array is too big, decompression succeeds. I would like to check the number of bytes written to the sink and throw an exception. How can I determine how many bytes have been written to the sink? Btw: I cannot use the "counter" filter because of the overhead involved in line counting and because the return value of its characters() method is "int". The buffers involved in my application require a 64 bit data type. Private base class basic_zlib_decompressor of class basic_gzip_decompressor has method total_out() which seems to return the value in question but its return type is also only an "int". Regards, Peter. #include <iostream> #include <stdexcept> #include <iomanip> #include <boost/iostreams/filtering_streambuf.hpp> #include <boost/iostreams/device/array.hpp> #include <boost/iostreams/filter/gzip.hpp> void decompress(const std::size_t p_bufferSize) { // decompressed string is "xy" const std::string s("\x1f\x8b\x08\x08\x58\xce\xf6\x5b\x02\x03\x78\x79\x00\xab\xa8\x04\x00\x99\x28\xe6\x8f\x02\x00\x00\x00",25); boost::iostreams::filtering_streambuf<boost::iostreams::output> filteringStreambuf; filteringStreambuf.push(boost::iostreams::gzip_decompressor()); const std::unique_ptr<char[]> buffer=std::make_unique<char[]>(p_bufferSize); filteringStreambuf.push(boost::iostreams::array_sink(buffer.get(),p_bufferSize)); boost::iostreams::write(filteringStreambuf,s.c_str(),s.size()); boost::iostreams::close(filteringStreambuf); } int main() { try { decompress(3); // works, although only 2 bytes are required, should be made to fail //decompress(2); // works, exactly fills the buffer //decompress(1); // throws exception "write area exhausted" as expected return 0; } catch (const std::exception& e) { std::cout << e.what() << std::endl; } return 1; }

2 2

Overcoming AST forward declaration (includes online example)
by Michael Powell 23 Nov '18

23 Nov '18

Hello, Please find the example posted here: http://wandbox.org/permlink/NI2Luvrw1HF7lF1E The couple of concerns I have in question at the moment are: * How to best handle variants throughout the grammar. Can I use std::variant? Do I need to use boost::variant? Are there additional Spirit features that make this doable? * Embedded in that question is what to do with "nil" or "empty statements" which occurs throughout the grammar at times. I wondered if "empty statement" could synthesize "nothing", literally, not contribute to a variant alternative, for instance. Other AST examples seemed to inject a "struct nil {}" pattern, so I figured maybe this was the better approach? * The real kerfuffle for me at the moment is the AST forward declaration. From what I gather in the protocol, this is an absolute must have. It most occur before Group, and is also used by Message. Thoughts? Suggestions? And, please, before you suggest there are "proto compilers" already available: yes, I know, I've been down that road. I am not looking to parse the proto itself, per se, but rather do some code generation for target language artifacts other than the proto itself. Toward which end, I am also investigating a protoc compiler plugin approach. But I figured, I'd pursue this as a viable path to solving the problem as well, notwithstanding the above challenges. Thanks in advance! Cheers, Michael Powell

3 6

Boost::Filesystem - Handling Unicode paths
by Richard Závodný 22 Nov '18

22 Nov '18

Hello, I have another problem. My program now failing when I want iterate directory which contain files with Unicode characters in it's name. Is there something I should know about? Also I want it to work on both Windows and POSIX platforms, even though I don't expect Unicode characters in POSIX enviroment. Thank you.

2 1

[Spirit] parsing double precision issues
by Michael Powell 22 Nov '18

22 Nov '18

Hello, I am continuing to work through my Protobuf parsing with Constant/Floating-Point tests. Double precision is rearing its ugly head and I am curious what's the best way to handle potentially determining a healthy epsilon given the expected parsed value. For the most part, I think it's going to work, but for the precision issues. Catch: REQUIRE( actual == expected ) with expansion: struct my::protobuf::ast::floating_point_t { 'val': 1.16624e+306, 'opt_sign': null } == struct my::protobuf::ast::floating_point_t { 'val': 1.16624e+306, 'opt_sign': null } with messages: Source: syntax = 'proto2';option L = 1.16624e+306; Delta was: 2.35309e+300 There was clearly a delta involved, most like a precision issue encountered during the parse. Without going into a great deal of depth, if possible: namespace my { namespace protobuf { namespace ast { using float_t = double; enum num_sign_t { sign_none /// '-' , sign_minus /// '+' , sign_plus }; // Which includes struct floating_point_t : numeric_t<float_t> { /* ... */ }; } } } // Without sign, dot required. // >>> TODO: TBD: Precision issue? Or an actual double parsing issue? <<< float_lit %= real_parser<ast::float_t, strict_ureal_policies<ast::float_t>>{}; floating_point_lit %= -num_lit_sign >> float_lit; qi::rule<It, ast::num_sign_t()> num_lit_sign; qi::rule<It, ast::float_t()> float_lit; qi::rule<It, ast::floating_point_t()> floating_point_lit; https://developers.google.com/protocol-buffers/docs/reference/proto2-spec#f… https://developers.google.com/protocol-buffers/docs/reference/proto2-spec#c… https://www.boost.org/doc/libs/1_68_0/libs/spirit/doc/html/spirit/qi/refere… Cheers, Michael Powell

1 4

[asio] UDP recv error handling
by Klebsch, Mario 22 Nov '18

22 Nov '18

Hello, When using boos asio async receiving, my received callback usually looks like this: void ReceiveCB(const boost::system::error_code& error, std::size_t bytes_transferred) { If (error) { fprintf(stderr, "recv() failes: %s\n", error.message().c_str()); return; } /* process data received */ s.async_receive( boost::asio::buffer(...), & ReceiveCB); } I stop calling async_receive() as soon as I get an error. This works good for TCP sockets. But with UDP sockets, recvfrom() can return e.g. the error 'connection refused' after I called sendto() to a peer machine, where no socket is (yet) bound to the destination port number. So, at least after the error 'connection refuxed', I'd better continue calling async_receive_from(). Are there any recommendations on how to decide, whether the receive callback function should re-initiate a receive operation after a receive error or not? Mario Klebsch -- Mario Klebsch Actia I+ME GmbH Mario.klebsch(a)ime-actia.de<mailto:Mario.klebsch@ime-actia.de> Dresdenstrasse 17/18 Fon: +49 531 38 701 716 38124 Braunschweig Fax: +49 531 38 701 88 Germany

1 0

Interprocess: limited boost::any in shared memory
by Ferguson, Neil D CTR (US) 21 Nov '18

21 Nov '18

Sirs and madams, I hope to use boost interprocess shared memory to pass complex and dynamic data structures between processes on a host efficiently. The structures will be comprised only of simple primitives (int, float, etc.), interprocess basic_string, interprocess containers (vectors and maps), containers of containers, and (possible deal killer) boost::any. From the interprocess documentation, it _looks_ like the preceding is doable, aside from boost::any. The boost::any objects will themselves contain only primitives, basic_string, or interprocess vectors of unsigned char. So it _looks_ like the data held by the any should be okay. My question: does boost::any use pointers, references, or other constructs that preclude the class from working in shared memory? Thanks for your advice. Neil Ferguson

3 2

boost::units - converting from one derived_dimension to another across systems (imperial to metric)
by Matt Vinson 21 Nov '18

21 Nov '18

Michael Powell: A) I hope to get Boost.Units to convert all these for me. I am replacing my own unit conversion classes with Boost.Units so there are no masking certain details, magic numbers, etc! Fingers Crossed. B) Boost.Units looks promising. Good to hear it has strong support. I'll keep at it. Thanks!// Steven Watanabe: Got it! You've been very patient and awesome. Thank you, yet again.I updated to this because I do need mass for density conversions:typedef boost::units::make_system< boost::units::us::inch_base_unit, boost::units::us::pound_base_unit, boost::units::us::pound_force_base_unit >::type ip_system; Any issues you see with boost::units::us::pound_base_unit for mass && boost::units::us::pound_force_base_unit for force? If I don't hear from you, I'll presume it's okay. My density unit testing* still passed after adding boost::units::us::pound_force_base_unit so I don't think there are issues. *each of these are converted to the other. enum class DENSITY : char { K_FT3 = 0, K_IN3 = 1, LB_FT3 = 2, LB_IN3 = 3, MT_M3 = 4, MT_CM3 = 5, MT_MM3 = 6, KG_M3 = 7, KG_CM3 = 8, KG_MM3 = 9, LAST = 10 }; On Tuesday, November 20, 2018, 9:09:45 PM CST, boost-users-request(a)lists.boost.org <boost-users-request(a)lists.boost.org> wrote: Send Boost-users mailing list submissions to boost-users(a)lists.boost.org To subscribe or unsubscribe via the World Wide Web, visit https://lists.boost.org/mailman/listinfo.cgi/boost-users or, via email, send a message with subject or body 'help' to boost-users-request(a)lists.boost.org You can reach the person managing the list at boost-users-owner(a)lists.boost.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Boost-users digest..." Today's Topics: 1. Re: boost::units - converting from one derived_dimension to another across systems (imperial to metric) (Michael Powell) 2. Re: Program Options documentation is anaemic (Gavin Lambert) 3. Re: boost::units - converting from one derived_dimension to another across systems (imperial to metric) (Steven Watanabe) 4. Re: Enquiry on boost.geometry and intersection() (Adam Wulkiewicz) ---------------------------------------------------------------------- Message: 1 Date: Tue, 20 Nov 2018 20:55:19 -0500 From: Michael Powell <mwpowellhtx(a)gmail.com> To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] boost::units - converting from one derived_dimension to another across systems (imperial to metric) Message-ID: <CAMEoF_GFTg_Fx4haDdb2i65fEaOB_hnG8QmrgshMSG5-0XT5mQ(a)mail.gmail.com> Content-Type: text/plain; charset="UTF-8" On Tue, Nov 20, 2018 at 8:47 PM Matt Vinson via Boost-users <boost-users(a)lists.boost.org> wrote: > > degski: I do not think am making the "nauseam" mistake. My issue is using Boost.Units correctly which I concede is difficult for me but I am reading the docs and trying to get it. > In our field of engineering, we use Kg as a force; not a mass. (We also use pound as a force; not a mass - for your "UK's Weights and Measures Act 1963" counterpart). That said, I should not have made the mistake of using Kg as a force in Boost.Units, it's true. Shame on me. > My task is to convert between lineal forces: k/ft, k/in, lb/ft, lb/in, kN/m, kN/cm, kN/m, N/m, N/cm, N/m, Metric ton/m, Metric ton/cm, Metric ton/mm, Kg/m, Kg/cm, Kg/mm. These are all force/length. Coming from an energy oil and gas background applying Boost.Units, that's a difficult conversation to have especially when "units" are used, but in fact are masking certain details, magic numbers, etc, confounding their dimensions. > Steven Watanabe: Thank you, again. > #1: I was not trying to say it's wrong; sorry. Just that I did not see 'length' and opted for the one that did. The unit's are correct, as you say. > #2: This is an error to start with Kg(force)/meter. I can start with N/meter. I've changed this variable name to newton_per_meter and the conversion factors. I can tell you this much; once you get reasonably proficient with Boost.Units, there is a strong compiler confidence in correctness once you have your dimensions, units, etc, meshing well together. By that I mean, in truth, compile time confidence. The compiler / Boost.Units will tell you when you have it wrong, and it will compile when you have it correct. That's a major plus in my book. Cheers, best of luck! > *.h----------------------------------------------------- > > namespace dimensional_analysis { > > typedef boost::units::length_base_dimension::dimension_type length_dimension; > > typedef boost::units::mass_base_dimension::dimension_type mass_dimension; > > typedef boost::units::make_system<boost::units::us::inch_base_unit,boost::units::us::pound_base_unit>::type ip_system; > > namespace lineal_force { > > typedef boost::mpl::divides<boost::units::force_dimension,boost::units::length_dimension>::type lineal_force_dimension; > > namespace imperial { > > //////////////// > > ////lb/in, right? > > ////boost::units::force_dimension = pound > > ////boost::units::length_dimension = in > > //////////////// > > typedef boost::units::unit<lineal_force_dimension,lengths::ip_system> lineal_force_unit; > > } > > namespace si { > > //////////////// > > ////N/m, right? > > ////boost::units::force_dimension = newton > > ////boost::units::length_dimension = meter > > //////////////// > > typedef boost::units::unit<lineal_force_dimension,boost::units::si::system> lineal_force_unit; > > } > > }//lineal_force > > }//dimensional_analysis > > *.cpp----------------------------------------------------- > > //Imperial lb/in to SI N/m > > BOOST_UNITS_DEFINE_CONVERSION_FACTOR( > > dimensional_analysis::lineal_force::imperial::lineal_force_unit, > > dimensional_analysis::lineal_force::si::lineal_force_unit, > > double, > > 175.1268369864); // exact conversion > > BOOST_UNITS_DEFAULT_CONVERSION( > > dimensional_analysis::lineal_force::imperial::lineal_force_unit, > > dimensional_analysis::lineal_force::si::lineal_force_unit); > > //SI N/m to Imperial lb/in > > BOOST_UNITS_DEFINE_CONVERSION_FACTOR( > > dimensional_analysis::lineal_force::si::lineal_force_unit, > > dimensional_analysis::lineal_force::imperial::lineal_force_unit, > > double, > > 0.1837185501); // exact conversion > > BOOST_UNITS_DEFAULT_CONVERSION( > > dimensional_analysis::lineal_force::si::lineal_force_unit, > > dimensional_analysis::lineal_force::imperial::lineal_force_unit); > > //Imperial to SI. This should convert lb/in to N/m and return 175.1268369864 (N/m) > > //But it does not. Its converting lb (mass) to Kg (mass), 0.454 > > const auto t2 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::si::lineal_force_unit>>( > > 1.0 * dimensional_analysis::lineal_force::imperial::lineal_force_unit::unit_type()); > > //Again, Imperial to SI. This should convert lb/in to N/m and return 175.1268369864 (N/m) > > //But it does not. It returns lb (mass) to Kg (mass) > > const auto t3 = boost::units::conversion_factor( > > dimensional_analysis::lineal_force::imperial::lineal_force_unit::unit_type(), > > dimensional_analysis::lineal_force::si::lineal_force_unit::unit_type()); > > //SI to Imperial. This should convert N/m to lb/in and return 0.1837185501 (lb/in) > > //But it does not. Its converting Kg (mass) to lb (mass), 2.205 > > const auto t1 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::imperial::lineal_force_unit>>( > > 1.0 * dimensional_analysis::lineal_force::si::lineal_force_unit::unit_type()); > > //So, I don?t know why the library is converting mass; I?ve tuned it to use boost::units::force_dimension/boost::units::length_dimension > > //I am doing something wrong where the library is not using force/length. > > //Below does work, mainly. > > //This is convert Si to SI and return value of 1.0 is correct. > > const auto t4 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::si::lineal_force_unit>>( > > 1.0 * boost::units::si::newton / boost::units::si::meter); > > //This convert lb/in to SI and return value is 175.1268369864 is correct. > > const auto t5 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::si::lineal_force_unit>>( > > 1.0 * boost::units::us::pound_force_base_unit::unit_type() / boost::units::us::inch_base_unit::unit_type()); > > //This converts lb/in to lb/in and return value is of 1.0 is correct. > > const auto t6 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::imperial::lineal_force_unit>>( > > 1.0 * boost::units::us::pound_force_base_unit::unit_type() / boost::units::us::inch_base_unit::unit_type()); > > //This is 2.205 and not correct. > > //It?s not converting SI-force/length to Imperial-force/length > > //Its converting Kg (mass) to lb (mass), 2.205 > > const auto t7 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::imperial::lineal_force_unit>>( > > 1.0 * boost::units::si::newton / boost::units::si::meter); > > //What have I done wrong? > > //Any help is appreciated. > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > https://lists.boost.org/mailman/listinfo.cgi/boost-users ------------------------------ Message: 2 Date: Wed, 21 Nov 2018 15:55:35 +1300 From: Gavin Lambert <boost(a)mirality.co.nz> To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] Program Options documentation is anaemic Message-ID: <3ab79a24-e6ff-e311-1d12-adbe5646a123(a)mirality.co.nz> Content-Type: text/plain; charset=utf-8; format=flowed On 20/11/2018 23:03, David Demelier wrote: > Reading the type_value documentation from Boost Program options feels like: > > ??? typed_value * composing(); > ??? Specifies that the value is composing. See the 'is_composing' > method for explanation. > > And the documentation of is_composing: > > ??? bool is_composing() const; > > Not sure if I know more what this function is supposed to do now. I agree that this seems somewhat unhelpful. FWIW a quick look elsewhere found https://www.boost.org/doc/libs/1_68_0/doc/html/program_options/tutorial.htm… which describes that option in more detail -- specifically that it's whether repeated parameters are merged or just replace the older value. > Also, I think this module/documentation should take a s/method/function/g. "Method" is the more common name for a method within a class. ------------------------------ Message: 3 Date: Tue, 20 Nov 2018 19:58:27 -0700 From: Steven Watanabe <watanabesj(a)gmail.com> To: Matt Vinson via Boost-users <boost-users(a)lists.boost.org> Cc: matt.vinson(a)sbcglobal.net Subject: Re: [Boost-users] boost::units - converting from one derived_dimension to another across systems (imperial to metric) Message-ID: <4f601999-f01c-0535-37a3-15e6e21d8331(a)gmail.com> Content-Type: text/plain; charset=utf-8 AMDG On 11/20/2018 06:46 PM, Matt Vinson via Boost-users wrote: > <snip> > <some reformatting to reduce line wrapping> > *.h----------------------------------------------------- > > namespace dimensional_analysis { > > ????typedef length_base_dimension::dimension_type length_dimension; > ????typedef mass_base_dimension::dimension_type mass_dimension; > > typedef make_system<inch_base_unit,pound_base_unit>::type ip_system; > This should be pound_force_base_unit. > ? namespace lineal_force { > ??? typedef mpl::divides<force_dimension,length_dimension>::type lineal_force_dimension;?????????? > > ??? namespace imperial { > > ????? //////////////// > ????? ////lb/in, right? > > ////boost::units::force_dimension =pound > ////boost::units::length_dimension = in > ????? //////////////// > ????? typedef unit<lineal_force_dimension,lengths::ip_system> lineal_force_unit; This unit is nonsensical because the ip_system as written is unable to represent the lineal_force_dimension. That this doesn't give a hard compiler error is a bug in the library. Once you fix ip_system, the conversions should be right. > ??? } > ??? namespace si { > ??? //////////////// > ??? ////N/m, right? > Yep. > ////boost::units::force_dimension = newton > ////boost::units::length_dimension = meter > ????? //////////////// > ????? typedef unit<lineal_force_dimension,si::system> lineal_force_unit; > ??? } > ? }//lineal_force > }//dimensional_analysis > > *.cpp----------------------------------------------------- > > //Imperiallb/in to SI N/m > The following conversion definitions are unnecessary and have no effect: > BOOST_UNITS_DEFINE_CONVERSION_FACTOR( > dimensional_analysis::lineal_force::imperial::lineal_force_unit, > dimensional_analysis::lineal_force::si::lineal_force_unit, > double, > 175.1268369864); // exact conversion > > BOOST_UNITS_DEFAULT_CONVERSION( > dimensional_analysis::lineal_force::imperial::lineal_force_unit, > dimensional_analysis::lineal_force::si::lineal_force_unit); > > //SI N/mto Imperial lb/in > > BOOST_UNITS_DEFINE_CONVERSION_FACTOR( > dimensional_analysis::lineal_force::si::lineal_force_unit, > dimensional_analysis::lineal_force::imperial::lineal_force_unit, > double, > 0.1837185501); // exact conversion > > BOOST_UNITS_DEFAULT_CONVERSION( > dimensional_analysis::lineal_force::si::lineal_force_unit, > dimensional_analysis::lineal_force::imperial::lineal_force_unit); > > <snip> > In Christ, Steven Watanabe ------------------------------ Message: 4 Date: Wed, 21 Nov 2018 04:09:11 +0100 From: Adam Wulkiewicz <adam.wulkiewicz(a)gmail.com> To: Zhang Qun <zhangq.rhy(a)gmail.com> Cc: boost-users(a)lists.boost.org Subject: Re: [Boost-users] Enquiry on boost.geometry and intersection() Message-ID: <9d3e335d-df1a-7627-af4f-a9d3fd8c22ff(a)gmail.com> Content-Type: text/plain; charset="utf-8"; Format="flowed" Please do not top-post. Zhang Qun?wrote: > Hi Adam > I think I have figured it out. Because of the precision, the two > polygons are not the same. > > That also explains that why sometimes the intersection() gives me two > intersection points looking "exactly" the same but if you look at the > double precision, they are actually two different points. In reality, > these two points can be safely considered the same point. I can solve > this by comparing the two points distance. However, sometimes also > because of the precision, the intersection() does not even give me any > intersection points especially when the line is right across the > vertex of the polygon. How do I solve this kind of problem? Could you paste the WKTs of geometries (with sufficient precision) [1] and say what do you get and what do you expect? [1] e.g. std::cout << std::setprecision(20) << bg::wkt(polygon) << std::endl; Adam

2 1

Enquiry on boost.geometry and intersection()
by Zhang Qun 21 Nov '18

21 Nov '18

Hi guys, first-time post here. Hello to everyone. I'm using boost.geometry to implement a project. I need to calculate the intersection between a line and a polygon. I know there is no infinite line concept in boost.geometry. So I try to use the segment to intersect with a polygon, however, it seems not supported yet. Is there any other workaround that I can implement the intersection between a line and a polygon? The line is like y=mx+b or ax + by + c = 0. Thanks. Ethan

2 6

boost::units - converting from one derived_dimension to another across systems (imperial to metric)
by Matt Vinson 21 Nov '18

21 Nov '18

degski: I do not think am making the "nauseam" mistake. My issue is using Boost.Units correctly which I concede is difficult for me but I am reading the docs and trying to get it. In our field of engineering, we use Kg as a force; not a mass. (We also use pound as a force; not a mass - for your "UK's Weights and Measures Act 1963" counterpart). That said, I should not have made the mistake of using Kg as a force in Boost.Units, it's true. Shame on me. My task is to convert between lineal forces: k/ft, k/in, lb/ft, lb/in, kN/m, kN/cm, kN/m, N/m, N/cm, N/m, Metric ton/m, Metric ton/cm, Metric ton/mm, Kg/m, Kg/cm, Kg/mm. These are all force/length. Steven Watanabe: Thank you, again.#1: I was not trying to say it's wrong; sorry. Just that I did not see 'length' and opted for the one that did. The unit's are correct, as you say. #2: This is an error to start with Kg(force)/meter. I can start with N/meter. I've changed this variable name to newton_per_meter and the conversion factors. *.h----------------------------------------------------- namespace dimensional_analysis{ typedef boost::units::length_base_dimension::dimension_type length_dimension; typedef boost::units::mass_base_dimension::dimension_type mass_dimension; typedef boost::units::make_system<boost::units::us::inch_base_unit,boost::units::us::pound_base_unit>::type ip_system; namespace lineal_force { typedef boost::mpl::divides<boost::units::force_dimension,boost::units::length_dimension>::type lineal_force_dimension; namespace imperial { //////////////// ////lb/in, right? ////boost::units::force_dimension =pound ////boost::units::length_dimension = in //////////////// typedef boost::units::unit<lineal_force_dimension,lengths::ip_system> lineal_force_unit; } namespace si { //////////////// ////N/m, right? ////boost::units::force_dimension = newton ////boost::units::length_dimension = meter //////////////// typedef boost::units::unit<lineal_force_dimension,boost::units::si::system> lineal_force_unit; } }//lineal_force }//dimensional_analysis *.cpp----------------------------------------------------- //Imperiallb/in to SI N/m BOOST_UNITS_DEFINE_CONVERSION_FACTOR( dimensional_analysis::lineal_force::imperial::lineal_force_unit, dimensional_analysis::lineal_force::si::lineal_force_unit, double, 175.1268369864); // exact conversion BOOST_UNITS_DEFAULT_CONVERSION( dimensional_analysis::lineal_force::imperial::lineal_force_unit, dimensional_analysis::lineal_force::si::lineal_force_unit); //SI N/mto Imperial lb/in BOOST_UNITS_DEFINE_CONVERSION_FACTOR( dimensional_analysis::lineal_force::si::lineal_force_unit, dimensional_analysis::lineal_force::imperial::lineal_force_unit, double, 0.1837185501); // exact conversion BOOST_UNITS_DEFAULT_CONVERSION( dimensional_analysis::lineal_force::si::lineal_force_unit, dimensional_analysis::lineal_force::imperial::lineal_force_unit); //Imperialto SI. This should convert lb/in to N/m andreturn 175.1268369864(N/m) //But itdoes not. Its converting lb (mass) to Kg(mass), 0.454 const auto t2 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::si::lineal_force_unit>>( 1.0 *dimensional_analysis::lineal_force::imperial::lineal_force_unit::unit_type()); //Again, Imperial to SI. This should convert lb/in to N/m and return 175.1268369864 (N/m) //But itdoes not. It returns lb (mass) to Kg(mass) const auto t3 = boost::units::conversion_factor( dimensional_analysis::lineal_force::imperial::lineal_force_unit::unit_type(), dimensional_analysis::lineal_force::si::lineal_force_unit::unit_type()); //SI toImperial. This should convert N/m tolb/in and return 0.1837185501 (lb/in) //But itdoes not. Its converting Kg (mass) to lb(mass), 2.205 const auto t1 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::imperial::lineal_force_unit>>( 1.0 *dimensional_analysis::lineal_force::si::lineal_force_unit::unit_type()); //So, I don’t know whythe library is converting mass; I’ve tuned it to use boost::units::force_dimension/boost::units::length_dimension //I am doing something wrongwhere the library is not using force/length. //Below does work, mainly. //This isconvert Si to SI and return value of 1.0 is correct. const auto t4 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::si::lineal_force_unit>>( 1.0 *boost::units::si::newton / boost::units::si::meter); //This convert lb/in to SI and return value is 175.1268369864 is correct. const auto t5 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::si::lineal_force_unit>>( 1.0 * boost::units::us::pound_force_base_unit::unit_type() / boost::units::us::inch_base_unit::unit_type()); //This converts lb/in to lb/in and return value is of 1.0 is correct. const auto t6 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::imperial::lineal_force_unit>>( 1.0 * boost::units::us::pound_force_base_unit::unit_type() / boost::units::us::inch_base_unit::unit_type()); //This is2.205 and not correct. //It’s notconverting SI-force/length to Imperial-force/length //Itsconverting Kg (mass) to lb (mass), 2.205 const auto t7 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::imperial::lineal_force_unit>>( 1.0 * boost::units::si::newton /boost::units::si::meter); //What have I done wrong? //Any help is appreciated.

3 2

Program Options documentation is anaemic
by David Demelier 21 Nov '18

21 Nov '18

Hello, Reading the type_value documentation from Boost Program options feels like: typed_value * composing(); Specifies that the value is composing. See the 'is_composing' method for explanation. And the documentation of is_composing: bool is_composing() const; Not sure if I know more what this function is supposed to do now. Also, I think this module/documentation should take a s/method/function/g. What's your thoughts on this? Regards, -- David

2 1

[Spirit] uint_parser inconsistent results
by Michael Powell 20 Nov '18

20 Nov '18

Hello, I am trying to figure out why the uint_parser yields what looks like raw characters in one instance, yet in another instance yields the original given phrase. What do I mean by that? I have a string-literal rule, subset of the Google protobuf v2 grammar, and the octal-escaped rule yields a raw character, but the "same" hex-escaped rule yields the given input string. Both rules are of type qi::rule<It, char()>. And the str_lit rule is qi::rule<It, std::string()>, basically. oct_esc %= '\\' >> uint_parser<unsigned char, 8, 3, 3>{}; hex_esc %= no_case["\\x"] >> uint_parser<unsigned char, 16, 2, 2>{}; char_val %= hex_esc | oct_esc | char_esc | ~char_("\0\n\\"); str_lit %= ("'" >> *(char_val - "'") >> "'") | ('"' >> *(char_val - '"') >> '"') ; struct escapes_t : qi::symbols<char, char> { escapes_t() { this->add("\\a", '\a') ("\\b", '\b') ("\\f", '\f') ("\\n", '\n') ("\\r", '\r') ("\\t", '\t') ("\\v", '\v') ("\\\\", '\\') ("\\'", '\'') ("\\\"", '"') ; } } char_esc; The only thing I can figure is that perhaps it has something to do with no-case having a secondary effect on the rule? I do not care which way it lands, per se, in either raw or original string, although landing in the raw, that is, unescaped, has some advantages, I suppose. However, it is a mystery to me how there are two different outcomes. Any thoughts? Suggestions? Thanks! Michael Powell

1 1

questions about visibility/dlls under mingw
by Robert Ramey 20 Nov '18

20 Nov '18

MINGW is the platform which runs gcc compilers under winsoze. I include all the visibility attribute in the "right" places with serialization build and tests. This is looking like it's passing on all platforms EXCEPT MINGW. I think MINGW uses the windows attributes, but I'm wonder if our boost setup uses the gcc macros. This would explain the bahavior I'm getting now. But honestly I really have no idea. here's the link to the appveyor results: https://ci.appveyor.com/project/RobertRamey/serialization/builds/20309631 Perhaps this is a config issue? or I'm doing wrong? I'm loath to much with this just for this one platform. Robert Ramey

3 12

Fwd: Boost::Filesystem - How to iterate, through the whole drive
by Richard Závodný 20 Nov '18

20 Nov '18

---------- Forwarded message --------- From: Richard Závodný <zavodnyrichard(a)gmail.com> Date: Sat, Nov 17, 2018, 3:59 PM Subject: Boost::Filesystem - How to iterate, through the whole drive To: <boost-users(a)lists.boost.org> Hey guys, I need iterate over all directories from starting path. If I start iterating from C:\some-dir it works very well, however if I try to iterate from C:\, it doesn't work. How can iterate through the whole drive? Thank you. Code is here: https://pastebin.com/mpsKJxH2 <https://pastebin.com/3J6FEMG5>. The problem I experience is commented right in the code section (line 1, 13 and 25).

4 7

boost::units - converting from one derived_dimension to another across systems (imperial to metric)
by Matt Vinson 20 Nov '18

20 Nov '18

Eisuke Kawashima: Thank You. I'll have a look. When I saw Boost.Units did not have imperial and we had to create it ourselves, I thought: the US is s 5 trillion dollar market, most of those markets need programming, all are on imperial. Boost.Units needs imperial and programmers would find and use it. Steven Watanabe: Thank You. This solution doesn't seem correct as it does not consider "length".... boost::units::derived_dimension< boost::units::mass_base_dimension, 1, boost::units::time_base_dimension, -2>::typeI thought I'd at it (L M T^-2 L-1) but this didn't do well.: typedef boost::units::derived_dimension< boost::units::length_base_dimension, 1, boost::units::mass_base_dimension, 1, boost::units::time_base_dimension, -2, boost::units::length_base_dimension, -1 >::type lineal_force_dimension; So, I tried the " typedef boost::mpl::divides<...>" solution as it has force and length. I am closer, I hope. *.h------------------------------------------------------------------------------------------------------------------------------------------ namespace dimensional_analysis { typedef boost::units::length_base_dimension::dimension_type length_dimension; typedef boost::units::mass_base_dimension::dimension_type mass_dimension; typedef boost::units::make_system< boost::units::us::inch_base_unit, boost::units::us::pound_base_unit >::type ip_system; namespace lineal_force { typedef boost::mpl::divides< boost::units::force_dimension, boost::units::length_dimension>::type lineal_force_dimension; namespace imperial { typedef boost::units::unit< lineal_force_dimension, dimensional_analysis ::ip_system > lineal_force_unit; typedef boost::units::quantity<lineal_force_unit, double> pound_per_in_quantity; BOOST_UNITS_STATIC_CONSTANT(pound_per_inch, pound_per_in_quantity); } namespace si { typedef boost::units::unit< lineal_force_dimension, boost::units::si::system > lineal_force_unit; typedef boost::units::quantity<lineal_force_dimension, double> kg_per_meter_quantity; BOOST_UNITS_STATIC_CONSTANT(kg_per_meter, kg_per_meter_quantity); } }//lineal_force }//dimensional_analysis *.cpp------------------------------------------------------------------------------------------------------------------------------------------ BOOST_UNITS_DEFINE_CONVERSION_FACTOR(dimensional_analysis::lineal_force::imperial::lineal_force_unit, dimensional_analysis::lineal_force::si::lineal_force_unit, double, 17.858); // exact conversion BOOST_UNITS_DEFAULT_CONVERSION(dimensional_analysis::lineal_force::imperial::lineal_force_unit, dimensional_analysis::lineal_force::si::lineal_force_unit); BOOST_UNITS_DEFINE_CONVERSION_FACTOR(dimensional_analysis::lineal_force::si::lineal_force_unit, dimensional_analysis::lineal_force::imperial::lineal_force_unit, double, 0.0559974); // exact conversion BOOST_UNITS_DEFAULT_CONVERSION(dimensional_analysis::lineal_force::si::lineal_force_unit, dimensional_analysis::lineal_force::imperial::lineal_force_unit); //This is not converting force/length and is converting si -> imperial mass (only) = 110.2. Needs to consider force/length, =50*0.0559974 auto t1 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::imperial::lineal_force_unit>>( 50.0 * dimensional_analysis::lineal_force::si::lineal_force_unit::unit_type()); / This is not converting force/length and i sconverting imperial -> si mass (only) = 22.7. Needs to consider force/length, =50*17.858 auto t2 = static_cast<boost::units::quantity<dimensional_analysis::lineal_force::si::lineal_force_unit>>( 50.0 * dimensional_analysis::lineal_force::imperial::lineal_force_unit::unit_type()); //This is again only converting mass and needs to convert force/length const auto t3 = boost::units::conversion_factor( dimensional_analysis::lineal_force::imperial::lineal_force_unit::unit_type(), dimensional_analysis::lineal_force::si::lineal_force_unit::unit_type()); On Monday, November 19, 2018, 12:46:57 PM CST, boost-users-request(a)lists.boost.org <boost-users-request(a)lists.boost.org> wrote: Send Boost-users mailing list submissions to boost-users(a)lists.boost.org To subscribe or unsubscribe via the World Wide Web, visit https://lists.boost.org/mailman/listinfo.cgi/boost-users or, via email, send a message with subject or body 'help' to boost-users-request(a)lists.boost.org You can reach the person managing the list at boost-users-owner(a)lists.boost.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Boost-users digest..." Today's Topics: 1. Re: boost::units - converting from one derived_dimension to another across systems (imperial to metric) (Eisuke Kawashima) 2. Re: Fwd: Boost::Filesystem - How to iterate, through the whole drive (Richard Z?vodn?) 3. Re: boost::units - converting from one derived_dimension to another across systems (imperial to metric) (Steven Watanabe) 4. Re: [release] Boost 1.69.0 Beta 1 (Marshall Clow) ---------------------------------------------------------------------- Message: 1 Date: Tue, 20 Nov 2018 02:23:10 +0900 From: Eisuke Kawashima <e.kawaschima+boost(a)gmail.com> To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] boost::units - converting from one derived_dimension to another across systems (imperial to metric) Message-ID: <CAHhxtD6A9Jwhv5amKnTa1bmNkD0U4_LGre8ySKFfQXK7w62oEQ(a)mail.gmail.com> Content-Type: text/plain; charset="UTF-8" Hi list, > I am having trouble converting from one derived_dimension to another across systems (imperial to metric). I'd like to convert, say, lb/in to, say, kg/m. I thought I would do the following but get a compiler error #: > > *.h-------------------------------------------------------------------------------- > namespace dimensional_analysis { > namespace lineal_force { > //lb/in > typedef boost::units::derived_dimension< > boost::units::us::pound_force_base_unit, 1, > boost::units::us::inch_base_unit, -1 > >::type lb_per_inch_dimension; > typedef boost::units::unit< > lb_per_inch_dimension, > dimensional_analysis::lengths::ip_system > > lb_per_inch_unit; > typedef boost::units::quantity<lb_per_inch_unit, double> lb_per_inch_quantity; > BOOST_UNITS_STATIC_CONSTANT(lbpin, lb_per_inch_quantity); > //kg/m > typedef boost::units::derived_dimension< > boost::units::si::kilogram_base_unit, 1, > boost::units::si::meter_base_unit, -1 > >::type kg_per_meter_dimension; > typedef boost::units::unit< > kg_per_meter_dimension, > boost::units::si::system > > kg_per_meter_unit; > typedef boost::units::quantity<kg_per_meter_unit, double> kg_per_meter_unit_quantity; > BOOST_UNITS_STATIC_CONSTANT(kgpm, kg_per_meter_unit_quantity); > }//lineal_force > }//dimensional_analysis > > *.cp ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > //Do I need these? > BOOST_UNITS_DEFINE_CONVERSION_FACTOR(dimensional_analysis::lineal_force::kg_per_meter_unit, dimensional_analysis::lineal_force::lb_per_inch_unit, double, 0.0559974); // exact conversion > BOOST_UNITS_DEFAULT_CONVERSION(dimensional_analysis::lineal_force::kg_per_meter_unit, dimensional_analysis::lineal_force::lb_per_inch_unit); > > //This does not compile# > const auto conv_factor_try0 = conversion_factor(dimensional_analysis::lineal_force::kg_per_meter_unit::unit_type(), dimensional_analysis::lineal_force::lb_per_inch_unit::unit_type()); > > # *\boost_1_68_0\boost\units\detail\conversion_impl.hpp(340): error C2672: 'conversion_factor': no matching overloaded function found (compiling source file...*.cpp) > > Any help is appreciated I opened a PR (https://github.com/boostorg/units/pull/32) to address such a situation; the following code ```cpp #include <iostream> #include <boost/units/base_units/us/inch.hpp> #include <boost/units/base_units/us/pound_force.hpp> #include <boost/units/io.hpp> #include <boost/units/physical_dimensions.hpp> #include <boost/units/systems/si.hpp> int main() { auto force_us{1.0 * boost::units::us::pound_force}; auto length_us{1.0 * boost::units::us::inch}; boost::units::quantity<boost::units::si::force, double> force_si{force_us}; boost::units::quantity<boost::units::si::length, double> length_si{length_us}; std::cout << force_us << " = " << force_si << '\n'; std::cout << length_us << " = " << length_si << '\n'; std::cout << force_us / length_us << " = " << force_si / length_si << '\n'; return 0; } ``` will print ``` 1 lbf = 4.44822 m kg s^-2 1 in = 0.0254 m 1 lbf in^-1 = 175.127 kg s^-2 ``` Best -- Eisuke Kawashima ------------------------------ Message: 2 Date: Mon, 19 Nov 2018 19:24:58 +0100 From: Richard Z?vodn? <zavodnyrichard(a)gmail.com> To: degski <degski(a)gmail.com>, boost-users(a)lists.boost.org Subject: Re: [Boost-users] Fwd: Boost::Filesystem - How to iterate, through the whole drive Message-ID: <d13622b0-9a68-d109-c26e-b60e3a5c45c8(a)gmail.com> Content-Type: text/plain; charset="utf-8"; Format="flowed" I just wanna try it again here, maybe somebody will shop up who knows where is the problem as I unfortunately couldn't fix it with degski (but still, thank you for your time :)). His example (can be found below) doesn't work on my system. The problem is I can't start iteration from the drive root (for example E:\), because it will iterate only the directory above (E:\projects\boost\build) the directory that the executable is located in (the executable is located in E:\projects\boost\build\Debug). What is weird that if I move the executable to the different directory (let's say C:\Users\USER_NAME\Downloads) it will still iterate only the build directory. I tried to play with Visual Studio -> PROJECT_NAME -> Properties -> Debugging -> Working Directory, but without a success. According to degski he has the value of this entry set to $(ProjectDir) which is the same value as mine. Thank you. On 11/18/2018 9:04 AM, degski wrote: > On Sun, 18 Nov 2018 at 05:31, Richard Z?vodn? via Boost-users > <boost-users(a)lists.boost.org <mailto:boost-users@lists.boost.org>> wrote: > > > > ---------- Forwarded message --------- > From: *Richard Z?vodn?* <zavodnyrichard(a)gmail.com > <mailto:zavodnyrichard@gmail.com>> > Date: Sat, Nov 17, 2018, 3:59 PM > Subject: Boost::Filesystem - How to iterate, through the whole drive > To: <boost-users(a)lists.boost.org <mailto:boost-users@lists.boost.org>> > > > Hey guys, I need iterate over all directories from starting path. > If I start iterating from C:\some-dir it works very well, however > if I try to iterate from C:\, it doesn't work. How can iterate > through the whole drive? Thank you. > > > Code is here: https://pastebin.com/mpsKJxH2 > <https://pastebin.com/3J6FEMG5>. The problem I experience is > commented right in the code section (line 1, 13 and 25). > > > This works for me, either with boost-1.68 (not that I think that > matters) or the STL-VC-15.9.1 (/std:c++17): > > #include <iostream> > #include <boost/filesystem.hpp> > > namespace fs = boost::filesystem; > > int main ( ) { > ??? for ( auto & p : fs::recursive_directory_iterator ( "d:\\" ) ) { > ??????? std::cout << p.path ( ) << '\n'; > ??? } > } > > Note that: "The iteration order is unspecified, except that each > directory entry is visited only once." > > degski > -- > /*/*?*/If something cannot go on forever, it will stop" - Herbert Stein*/

4 6

Making an ASIO asynchronous operation from flock()
by Cristian Morales Vega 20 Nov '18

20 Nov '18

So I need to flock (http://man7.org/linux/man-pages/man2/flock.2.html) something (pre-existing flock in other piece of software to interoperate with) and I though: "I think I'm actually starting to understand ASIO, let's make a proper ASIO asynchronous operation with flock". Long story short, I now know better: I will never get ASIO. So my main issues are with the background thread. According to https://www.boost.org/doc/libs/develop/doc/html/boost_asio/overview/core/th… "the threads ... must block all signals". OK, it makes sense, but... - I can make pthread_sigmask() the first thing once the std::thread starts executing. But, I can't really guarantee the thread will never receive a signal, can I? There is a small amount of time between the thread starting to be able to receive signals and pthread_sigmask() doing its job. Modifying the signal mask before the background thread is created (so also from the "not-background" thread) doesn't seem a lot better. - How do I cancel the asynchronous operation? flock() is blocking, not a lot I can do to unblock it. I could send a signal to the background thread, but... they must be blocked, so no. I can't join the thread while it's blocked in flock(). So... should it be detached? I could then maybe just destroy the std::thread, but I still need to call the handler with boost::asio::error::operation_aborted... So, my question: I'm making it more difficult than it is? There is some pattern I should be following which makes all this simple? See what I have below (sorry for the camel case) ------------------------------------------------------------------------------- #include <boost/asio.hpp> #include <boost/beast/core/bind_handler.hpp> #include <boost/system/error_code.hpp> #include <boost/system/system_error.hpp> #include <fcntl.h> #include <iostream> #include <sys/file.h> #include <sys/stat.h> #include <sys/types.h> #include <thread> namespace asio = boost::asio; using error_code = boost::system::error_code; using system_error = boost::system::system_error; class FLockablePosixDescriptor : public asio::posix::descriptor { public: enum class FlockType : int { SHARED = LOCK_SH, EXCLUSIVE = LOCK_EX }; using asio::posix::descriptor::descriptor; FLockablePosixDescriptor(FLockablePosixDescriptor &&) = default; FLockablePosixDescriptor &operator=(FLockablePosixDescriptor &&) = default; ~FLockablePosixDescriptor(); template <typename FLockToken> BOOST_ASIO_INITFN_RESULT_TYPE(FLockToken, void(error_code)) asyncFLock(FlockType type, FLockToken &&token); void cancel(); void cancel(error_code &ec); private: template <typename FLockHandler> void doFLock(int fd, FlockType type, FLockHandler &handler); asio::io_context mBackgroundContext{1}; std::thread mThread; }; FLockablePosixDescriptor::~FLockablePosixDescriptor() { mBackgroundContext.stop(); mThread.join(); } template <typename FLockToken> BOOST_ASIO_INITFN_RESULT_TYPE(FLockToken, void(error_code)) FLockablePosixDescriptor::asyncFLock(FlockType type, FLockToken &&token) { asio::async_completion<FLockToken, void(error_code)> init(token); mBackgroundContext.post([this, fd = native_handle(), type, handler = std::move(init.completion_handler), work = asio::make_work_guard(get_executor())] { doFLock(fd, type, handler); }); mThread = std::thread([this] { mBackgroundContext.run(); }); return init.result.get(); } template <typename FLockHandler> void FLockablePosixDescriptor::doFLock(int fd, FlockType type, FLockHandler &handler) { error_code ec; if (flock(fd, static_cast<int>(type)) == -1) { ec = error_code(errno, boost::system::system_category()); } asio::post(get_executor(), boost::beast::bind_handler(handler, ec)); } void FLockablePosixDescriptor::cancel() { error_code ec; cancel(ec); if (ec) { throw system_error(ec, "cancel"); } } void FLockablePosixDescriptor::cancel(error_code &ec) { // TODO: Cancel flock asio::posix::descriptor::cancel(ec); } int main() { boost::asio::io_context ioc; int fd = open("l", O_RDONLY); FLockablePosixDescriptor desc(ioc, fd); desc.asyncFLock(FLockablePosixDescriptor::FlockType::SHARED, [](const error_code &ec) { std::clog << "Done " << ec << std::endl; }); ioc.run(); } -------------------------------------------------------------------------------

2 2

[release] Boost 1.69.0 Beta 1
by Marshall Clow 19 Nov '18

19 Nov '18

Boost release 1.69.0 beta 1 is now available at: <https://dl.bintray.com/boostorg/beta/1.69.0.beta1/source/> The SHA256 checksums are as follows: ee0ecd7d31f58474c1e0210089c9e66bd878d4d1e7436ac511e359aa4a9d3e86 ./boost_1_69_0_b1.7z 3e25c46f2171799caabbeb419ba7859fffb62208f3a1c80798713377ab07af0e ./boost_1_69_0_b1.tar.bz2 71f4b57175058af1b8c320971cf29226e5a652931a679f7e1c086655147ecafb ./boost_1_69_0_b1.tar.gz ec9ef7d2c9f0d41f560769e67bc7ff207cc999243a7dd6c3f6bcfbdbf0827a7b ./boost_1_69_0_b1.zip For details of what's in the release, see < https://www.boost.org/users/history/version_1_69_0.html>. Please download the beta, give it a try, and report any problems you encounter. Thanks, -- The Boost Release Team

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boost::units - converting from one derived_dimension to another across systems (imperial to metric)
by Matt Vinson 19 Nov '18

19 Nov '18

Thanks for input...Ok, I have errors creating a 'lineal force unit'. In our branch of engineering, we have kips****/ft, kips/in, lbs/foot, lbs/in, kN/meter, Kn/cm, KN/mm, N/meter, N/cm, N/mm, Metric Ton/meter, Metric Ton/cm, Metric Ton/mm, KiloGram/meter $, KiloGram/cm, KiloGram/mm, etc....All these units* are loosing force divided by length. After all the appreciated input in this thread, I thought I'd try this but it does not compile*** probably because force is "L M T^-2" and length is "L" which is not correct: //Lineal Force typedef boost::units::derived_dimension< boost::units::force_dimension, 1, boost::units::length_dimension, -1 >::type lineal_force_dimension; How can I use Boost.Units to convert one force/length to another force/length: say, lb/in to, say, kg/m? *not Boost.Units**, the units in the engineering math equation**A set of base units raised to rational exponents, e.g. m^1, kg^1, m^1/s^2. *** ...\boost_1_68_0\boost\mpl\aux_\preprocessed\plain\less.hpp(20): error C2039: 'value': is not a member of 'boost::units::detail::dimension_list_tag' ****1000 lbs force = kips***** Here is a table in Wiki about converting between lbs and kilogram. Kilogram in Boost.Units is a mass not a force so I need to create a kilogram force and I did that when I converted "Forces" $ in another task... $.h struct metric_ton_base_unit : boost::units::base_unit<metric_ton_base_unit, boost::units::force_dimension, 7> { }; typedef metric_ton_base_unit::unit_type metric_ton_unit; BOOST_UNITS_STATIC_CONSTANT(metric_ton, metric_ton_unit); typedef boost::units::quantity<metric_ton_unit> metric_ton_quantity; // typedef boost::units::make_scaled_unit<metric_ton_unit, boost::units::scale<10, boost::units::static_rational<-3>>>::type kg_force_unit; BOOST_UNITS_STATIC_CONSTANT(kg_force, kg_force_unit); typedef boost::units::quantity<kg_force_unit> kg_quantity;.cpp BOOST_UNITS_DEFINE_CONVERSION_FACTOR(dimensional_analysis::force::metric_ton_base_unit, dimensional_analysis::force::newton_base_unit, double, 9806.65); // exact conversion BOOST_UNITS_DEFAULT_CONVERSION(dimensional_analysis::force::metric_ton_base_unit, dimensional_analysis::force::newton_base_unit);% $ lb/in to kg/m: Google: convert lb/in to kg/m

2 1

boost::units - converting from one derived_dimension to another across systems (imperial to metric)
by Matt Vinson 19 Nov '18

19 Nov '18

I am having trouble converting from one derived_dimension to another across systems (imperial to metric). I'd like to convert, say, lb/in to, say, kg/m. I thought I would do the following but get a compiler error #: *.h-------------------------------------------------------------------------------- namespace dimensional_analysis { namespace lineal_force { //lb/in typedef boost::units::derived_dimension< boost::units::us::pound_force_base_unit, 1, boost::units::us::inch_base_unit, -1 >::type lb_per_inch_dimension; typedef boost::units::unit< lb_per_inch_dimension, dimensional_analysis::lengths::ip_system > lb_per_inch_unit; typedef boost::units::quantity<lb_per_inch_unit, double> lb_per_inch_quantity; BOOST_UNITS_STATIC_CONSTANT(lbpin, lb_per_inch_quantity); //kg/m typedef boost::units::derived_dimension< boost::units::si::kilogram_base_unit, 1, boost::units::si::meter_base_unit, -1 >::type kg_per_meter_dimension; typedef boost::units::unit< kg_per_meter_dimension, boost::units::si::system > kg_per_meter_unit; typedef boost::units::quantity<kg_per_meter_unit, double> kg_per_meter_unit_quantity; BOOST_UNITS_STATIC_CONSTANT(kgpm, kg_per_meter_unit_quantity); }//lineal_force }//dimensional_analysis *.cp ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- //Do I need these? BOOST_UNITS_DEFINE_CONVERSION_FACTOR(dimensional_analysis::lineal_force::kg_per_meter_unit, dimensional_analysis::lineal_force::lb_per_inch_unit, double, 0.0559974); // exact conversion BOOST_UNITS_DEFAULT_CONVERSION(dimensional_analysis::lineal_force::kg_per_meter_unit, dimensional_analysis::lineal_force::lb_per_inch_unit); //This does not compile# const auto conv_factor_try0 = conversion_factor(dimensional_analysis::lineal_force::kg_per_meter_unit::unit_type(), dimensional_analysis::lineal_force::lb_per_inch_unit::unit_type()); # *\boost_1_68_0\boost\units\detail\conversion_impl.hpp(340): error C2672: 'conversion_factor': no matching overloaded function found (compiling source file...*.cpp) Any help is appreciated

8 8

Bad link in https://www.boost.org/community/groups.html page
by Dan Field 19 Nov '18

19 Nov '18

The https://www.boost.org/community/groups.html page discusses various boost mailing lists. In the section discussing the Users mailing list, there's a link to browse Gmain's searchable archive. This link is dead.

1 0

Broken link in Getting Started Page
by David Demelier 19 Nov '18

19 Nov '18

Hello, The link: (an up-to-date list is always available in the Boost.Build documentation). In the getting started page is broken and ends in 404. https://www.boost.org/doc/libs/1_68_0/more/getting_started/windows.html Regards,

1 0

[Variant] Bug assigning similar, but different concrete types during assignment / ctor relay
by Michael Powell 18 Nov '18

18 Nov '18

Hello, I've got a Boost.Variant confusion going on during ctor relay. I have two types participating in the Variant, an Integer type and a Floating Point type. Both are Numeric as a base class. i.e. something like: template<typename T> struct numeric {}; struct integer : numeric<long> {}; struct floating_point : numeric<double> {}; Then: using constant_value = boost::variant<..., floating_point, integer, ...>; Somewhere during the handling, I have a test case in which I have a constant_value{} starting out in life as an integer{}. However, somewhere during handling, variant is misinterpreting integer (which=3) as a floating_point (which=2). This is incorrect, of course. I could force the issue, I suppose and re-set the value to the integer, but I'd like to understand the issue. I think it's a bug in variant, or perhaps a "feature" confusing integer with floating_point along base class numeric lines? Any ideas

2 5

[release] Boost 1.69.0 Beta 1 Release Candidate 3
by Marshall Clow 17 Nov '18

17 Nov '18

[ Ok, I've rebuilt the RC - and it contains only the changes to function and MPL ] The release candidates for the third 1.69.0 beta release are now available at: <https://dl.bintray.com/boostorg/beta/1.69.0.beta1.rc3/source/> The release notes are not yet final. The SHA256 checksums are as follows: ee0ecd7d31f58474c1e0210089c9e66bd878d4d1e7436ac511e359aa4a9d3e86 ./boost_1_69_0_b1_rc3.7z 3e25c46f2171799caabbeb419ba7859fffb62208f3a1c80798713377ab07af0e ./boost_1_69_0_b1_rc3.tar.bz2 71f4b57175058af1b8c320971cf29226e5a652931a679f7e1c086655147ecafb ./boost_1_69_0_b1_rc3.tar.gz ec9ef7d2c9f0d41f560769e67bc7ff207cc999243a7dd6c3f6bcfbdbf0827a7b ./boost_1_69_0_b1_rc3.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Boost Release Managers

2 2

Re: [Boost-users] [boost] [release] Boost 1.69.0 Beta 1 Release Candidate 2
by Marshall Clow 16 Nov '18

16 Nov '18

On Thu, Nov 15, 2018 at 11:37 AM Robert Ramey via Boost < boost(a)lists.boost.org> wrote: > On 11/14/18 2:50 PM, Marshall Clow via Boost wrote: > > Marshall, > > I would like to merge development of the serialization library into the > master if there is an opportunity to do so. If not, I'll just wait > until after the release. > After the beta release, sure. > I know you've complained about merging w/o permission. I'm not a git > guru but can't you tag the current state and work with that > independently of what anyone subsequently merges. Also there's creating > a branch for the merge. Also the possibility of keeping the release > candidate on your own machine and only pulling what you want to > explictly merge. Just food for thought? > Or you can merge to release locally and not push those changes until later. -- Marshall

2 1

process group object creation fail with version-1.67, 1.68
by dinesh kumar 16 Nov '18

16 Nov '18

Hi Team, I would like to take this to your notice, as the boost process group object creation is failing, in windows with ${SUBJECT} versions. I've tried 1.66, 1.69-b1-canadiate2 both are working fine. #include <boost/process.hpp> #include <iostream> int main() { try { boost::process::group grp; } catch (std::exception &e) { std::cout << e.what(); } return 0; } *Output* SetInformationJobObject() failed: The handle is invalid. Visual studio version is: 15.8.5 -- Regards, Dinesh manojadinesh.blogspot.com

1 0

[release] Boost 1.69.0 Beta 1 Release Candidate 2
by Marshall Clow 16 Nov '18

16 Nov '18

The release candidates for the second 1.69.0 beta release are now available at: <https://dl.bintray.com/boostorg/beta/1.69.0.beta1.rc2/source/> The release notes are not yet final. The SHA256 checksums are as follows: 77827b25121159a4e65cfbdf19713e2d589fce267fd6f08615a453d24753c9d3 ./boost_1_69_0_b1_rc2.7z ea05c6e01c856369afdab1f6c075e06fb0f965ab1c247f753ed5c951a9db4e71 ./boost_1_69_0_b1_rc2.tar.bz2 b393a73cf084be716c40ef346cfacb1c95e7b14637e8385eeeb50774dd0b99ed ./boost_1_69_0_b1_rc2.tar.gz 74c0c0a19a700fee2b4f434bb7df50840642e3c35924e85864b278bd519af062 ./boost_1_69_0_b1_rc2.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Boost Release Managers

2 5

[Optional] Lazy initialized optional
by Michael Powell 14 Nov '18

14 Nov '18

Hello, I am looking into deriving from boost::optional and adding lazy initialization capability. I can arrange a constructor, or whatever, to inject an appropriate factory method, functional callback, etc, that's no problem. >From the boost::optional perspective, I'd like to override a key method (or methods, hopefully not too many) in order to inject that factory provided value. I'm thinking optional::get? Unless there's a better override for that? Cheers, Michael Powell

3 3

[release] Boost 1.69.0 Beta 1 Release Candidate 1
by Marshall Clow 14 Nov '18

14 Nov '18

The release candidates for the first 1.69.0 beta release are now available at: <https://dl.bintray.com/boostorg/beta/1.69.0.beta.1.rc1/source/> The release notes are not yet available. The updated documentation is not yet available. [ They will be available in a day or two. ] The SHA256 checksums are as follows: db6b346389714647490d6503db881e4178dd8cd498f850999bebf72cacd4c4ed boost_1_69_0_b1_rc1.7z d128c82351becbd37a02b9b4818994d3f66ff8bdbc0a18838206f4c070db97af boost_1_69_0_b1_rc1.tar.bz2 4df6262db53cfd0d0f934cb126f7e48e94872fe4441cbac6bf72a43bfb136a45 boost_1_69_0_b1_rc1.tar.gz e2908e33cc15f92cda06ddde6a3da43b18967a83105355571fc3cf6e75820c7f boost_1_69_0_b1_rc1.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Boost Release Managers

7 16

Trouble building boost
by Vipin Verma 13 Nov '18

13 Nov '18

Hello I have tried building boost on my Windows as well as Ubuntu system, but I am not able to make it work. Could you please help me? Here is a post with details about Windows - https://stackoverflow.com/questions/53273860/opennero-windows-could-not-fin… Here is a post about Ubuntu - https://stackoverflow.com/questions/53151130/opennero-ubuntu-process-finish… -- Regards Vipin Verma <https://www.linkedin.com/in/vipin8169> BlueSapling Technologies Pvt Ltd. <https://bluesapling.com/> +1-480-410-1673

1 0

[Variant] Minimum implementation to be variant friendly
by Michael Powell 13 Nov '18

13 Nov '18

Hello, What's the minimum implementation a struct needs to fulfill in order to be boost::variant friendly? Things like, does it need to support perfect forwarding? An assignment operator? And so on. Thanks! Michael Powell

3 4

[Spirit] Qi int_parser rejecting a negative signed std::intmax_t
by Michael Powell 12 Nov '18

12 Nov '18

Hello, qi::int_parser works fine for a positive signed hex radix integer, but is failing for a negative signed hex radix integer. My integer type is std::intmax_t, which on this platform I think is long long. Is there an integer width constraint? And/or a signage problem? Do I need to enable BOOST_HAS_LONG_LONG? Or is that enabled by default? Cheers, thanks! Michael Powell

2 7

Boost 1.68.0 contains only python 3.7 library, no python 2.7 library?
by Heng Zhou 10 Nov '18

10 Nov '18

Hi, I installed Boost 1.68.0 recently from Windows x64 pre-compiled binary "boost_1_68_0-msvc-14.0-64.exe" downloaded from https://urldefense.proofpoint.com/v2/url?u=https-3A__sourceforge.net_projec…. Then, I noticed that this version of Boost contains only python 3.7 library because the filenames under C:\local\boost_1_68_0\lib64-msvc-14.0 are only boost_python37-vc140-mt-.... This caused errors from building a third-party library which tries to link Boost python 2.7 library (i.e., tries to find file boost_python27-vc140-mt-...) . So what is matter? Does Boost decide to stop supporting python 2.7 since version 1.68.0, or is Boost python 2.7 library located somewhere else using some hard-to-recognize filename? I'm using Windows 10, VS2015 and have only python 2.7 installed. Thank you for your help with this issue.

2 1

[Format] Possible to format numeric values using radix?
by Michael Powell 09 Nov '18

09 Nov '18

Hello, For instance, given a numerical value, I'd like to specify the Radix, whether to format octal or hex. Thanks in advance! Best regards, Michael Powell

1 1

[DLL] BOOST_DLL_ALIAS not working on MinGW-w64
by David Demelier 09 Nov '18

09 Nov '18

Hello, I'm using boost 1.68 on MinGW-w64 (Windows 10). I'm trying a simple plugin that works fine under Linux and FreeBSD However, on Windows boost::dll::import_alias triggers an exception: terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::system::system_error> >' what(): boost::dll::shared_library::get() failed: The specified procedure could not be found This is the plugin (plugin.cpp) #include <iostream> #include <boost/dll.hpp> namespace custom { void my_function() { puts("CALLED"); } } // !custom BOOST_DLL_ALIAS(custom::my_function, my_function) I compile using: g++ -std=c++17 -shared -o plugin.dll plugin.cpp -lboost_system-mt And the simple main.cpp file: #include <boost/dll.hpp> int main() { using my_function = void (); auto f = boost::dll::import_alias<my_function>("./plugin.dll", "my_function"); } What's strange, nm does not report any kind of unmangled symbols related to "my_function": $ nm plugin.dll | grep my_function 0000000067e81422 t _GLOBAL__sub_I__ZN6custom11my_functionEv 0000000067e813b0 T _ZN6custom11my_functionEv It should contains something starting with boostdll_ isn't it? What's happening there? Do I miss something? -- David

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[Spirit] Qi lexeme only taking the first word
by Michael Powell 08 Nov '18

08 Nov '18

Hello, I've got a couple of rules that are perplexing to me. First, rule<It, std::string(), St> id %= lexeme[qi::alpha >> *char_("A-Za-z0-9_")]; In and of itself, id is working fine. Then I've got a "full id": rule<It, full_id_t(), St> full_id %= id >> *(char_('.') >> id); Where: struct full_id_t { std::string val; }; full_id_t::val is quite intentional for reasons elsewhere in the grammar. The perplexity comes in, it seems lexeme is only shaving off the first word as the val. For instance, parsing "two.oranges.red.test", I receive back "two" in the AST. Perhaps I should defer specifying the lexeme part of id until later? Thoughts? Suggestions? Thank you! Best regards, Michael Powell

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Build/use Boost without ICU
by braden 08 Nov '18

08 Nov '18

How does one build (and use) Boost without ICU when ICU is installed (i.e., visible to b2)? I am am bootstrapping with: ...which shows: Seems reasonable so far. Building happens with: ...which shows: In spite of passing "--disable-icu -sboost.locale.icu=off" to b2, I still see Boost.Locale getting built with -DBOOST_LOCALE_WITH_ICU=1; e.g.: What's the correct way to do this? ----- Braden McDaniel braden(a)endoframe.com -- Sent from: http://boost.2283326.n4.nabble.com/Boost-Users-f2553780.html

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Newby help with Boost::Log
by Davies, John 08 Nov '18

08 Nov '18

I'm using Boost Log to capture all keypresses in my embedded device. I want to be able to store at most 3 files of a certain size and rotate them. That's working. My problem is a scenario like this: The device is inserting data into Log_009.log which is in the base folder. In the log folder are Log_006.log, Log_007.log, and Log_008.log. The program stops and restarts. This may be due to some keypress that was logged in Log_009.log. When it restarts, it clears out Log_009.log and starts it over - losing the last logged keypresses Ideally, I'd like Boost Log to just keep appending to Log_009.log, but my reading online says that this isn't possible. My second favorite solution would be that Log_009 gets rotated and Log_010.log is started. Anything so I don't lose data. Here is my configuration: logging::add_common_attributes(); logging::add_file_log ( keywords::file_name = "KeyLog_%3N.log", keywords::target = "./Logs", keywords::rotation_size = 500, // 10 * 1024 * 1024, keywords::format = "[%TimeStamp%]: %Message%", keywords::auto_flush = true, keywords::min_free_space = 30 * 1024 * 1024, boost::log::keywords::max_size = 20 * 1024, keywords::enable_final_rotation = true, keywords::scan_method = sinks::file::scan_matching, keywords::max_files = 3 ); Can you see what I'm missing? If a program exits via a crash, does final rotation occur? Maybe I need something like enable_initial_rotation. Thanks for the help, 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.

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Deadline for 1.69.0 beta extended
by Marshall Clow 07 Nov '18

07 Nov '18

The deadline for closing the master branch for the 1.69.0 beta has been extended until Friday, November 9th. The final release date has not been changed. -- Marshall (who is at a WG21 meeting all week)

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Boost Dinner at ISO meeting in San Diego
by Jon Kalb 07 Nov '18

07 Nov '18

If you are in, or close to, the San Diego area, please join us tomorrow (Wednesday) evening at 18:00 at Gordon Biersch (5010 Mission Center Rd, San Diego, CA 92108) for a Boost Interest Dinner. https://gordonbiersch.com/locations/san-diego/ We’ll be in the patio area. Thanks. Jon

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[Boost.Asio] Allow/DisAllow client connection to Serveur.
by Gadamatik 06 Nov '18

06 Nov '18

Hello to all, I'm trying to develop a serveur that will allow/disallow a client to access internet according a ticket provided to him, just a kind of Raduis. Because Boost.Asio deal with OS, so I just want the client get access to internet if, only if he has a ticket that my server will provide him. I'm looking the way to do this but i'm really stick at this point. I'll really appreciate your strong help to find a way, just a way. I'm working on Windows. Thanks in advance. ----- La patience guide mes raisons -- Sent from: http://boost.2283326.n4.nabble.com/Boost-Users-f2553780.html

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Regarding certificate verification using Asio
by David Demelier 05 Nov '18

05 Nov '18

Hello, This is more a general question about certificates verification in SSL contexts. I hope this is not too much offtopic. I know how asymmetric encryption works, but I never dig a lot into the process of certificates verification. I know how certificate checks are made with browsers, the server must have a certificate signed by a trusted CA. But then, I must admit that I don't know many more. For example, A lot of Linux package managers use package signing to be sure that packages downloaded are correctly built from the vendor. But this is another topic I guess. Now, for example, I would like to create my own server process and my own client. They are not open to the internet, so no need to buy trusted authority certificates. So by generating self-signed certificate and private key file. The server can run. The question is: how the client be sure that it is connecting to the right server? Do this client needs to have the same certificate on its local machine and use it? If yes, should I use ssl::context::load_verify_file and ssl::verify_peer and I'm done? If you have some resources to advice me on the certificate check mechanisms, please give me. Regards -- David

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Compile Boost 1.64 on ARM64
by Lior Koskas 04 Nov '18

04 Nov '18

Hello, I'm trying to compile boost on my 64 ARM machine. In order to compile I ran this command ./bootstrap.sh && ./b2. When I'm looking at the output of the b2 program, I noticed that it does not recognize my machine as ARM architecture: Performing configuration checks - 32-bit : no (cached) - 64-bit : yes (cached) - arm : no (cached) - mips1 : no (cached) - power : no (cached) - sparc : no (cached) - x86 : yes (cached) How can I enforce boost to compile as ARM64 architecture? Thank you, -- Lior

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Missing boost/test/utils/trivial_singleton.hpp header
by Martin Beseda 04 Nov '18

04 Nov '18

Hello everybody, I'm beginning with the Boost.Test library and I wanted to use it together with Turtle Mock library <http://turtle.sourceforge.net/>, as it claims to be developed specifically for usage with Boost. The problem is, I'm getting the error, that boost/test/utils/trivial_singleton.hpp is missing. I'm using other Boost headers with no problem, so I had a look at the codes and it seems, that trivial_singleton.hpp header is not there. Also, I couldn't find him in the online repository. Was the header relocated or removed? Thank you very much for the information, Martin

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[release] 1.69.0 closed for major changes
by Marshall Clow 01 Nov '18

01 Nov '18

The master branch is now closed for new libraries and breaking changes, and will be closing for the beta in one week. Also, if you're ready, you can also add your libraries' changes to the release notes at: < https://github.com/boostorg/website/blob/master/feed/history/boost_1_69_0.q… > After editing the release notes, you should get a form to create a pull request, remember to submit it, otherwise I won't see your change. Thanks, -- The Boost Release Team

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Web based C++ compiler with Boost support
by Michael Powell 01 Nov '18

01 Nov '18

Hello, Does anyone happen to know of a decent web based C++ compiler with Boost support? Specifics, if possibly, include support for MSVC, especially VS2017 C++, Spirit, probably C++17 as well, etc. I know that's probably asking for a lot, but my searches aren't turning up very much, or it is getting confused with literally "building Boost", which is a bit OT. :-) Thanks! Best regards, Michael Powell

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Roughed in Proto2 Spirit parser
by Michael Powell 31 Oct '18

31 Oct '18

Hello, I'm working on a Proto2 Spirit parser. Right now it's really roughed in. There is no AST at the moment. That's TBD; right now I am focused on just getting the build to work. https://gcc.godbolt.org/z/_nBsKi The code is there, but the compiler driving the web site is choking on Spirit. I put the rules in up front; probably ambitious on my part, and am finding an error on: _range %= _int_lit >> -(lit("to") >> (_int_lit | lit("max")); Severity Code Description Project File Line Suppression State Error C1075 '{': no matching token found Kingdom.OrTools.Sat.Params.Generator g:\source\kingdom software\kingdom.ortools\standard\src\kingdom.ortools.sat.params.generator\proto_parser.cpp 205 The Proto2 grammar states: range = intLit [ "to" ( intLit | "max" ) ] I'm considering pairing it back significantly and building the grammar up gradually to make sure it all builds. That's probably a sounder approach anyway. Eventually I want to build up the AST in such a way as to facilitate generating some boilerplate adapter code in my target language (C#). Thoughts? Best regards, Michael Powell https://developers.google.com/protocol-buffers/docs/reference/proto2-spec

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