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Passing -D options with b2 to ASIO when compiling with mingw64 ucrt64?
by Joost Kraaijeveld 17 Mar '25

17 Mar '25

Hi, I try to compile Boost with MingW64 with ucrt64. I get warnings saying I should define _WIN32_WINNT with 0x0601 or higher and an error saying I must define USE_W32_SOCKETS. Is it possible to pass these on a command line to b2 or otherwise, without interfering with Boost's source? TIA -- Groeten, Joost

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release] Boost 1.88.0 beta 1 released
by Marshall Clow 16 Mar '25

16 Mar '25

Boost release 1.88.0 beta 1 is now available at: https://archives.boost.io/beta/1.88.0.beta1/source/ The SHA256 checksums are: bc4948bc664fde0c2142badae2679a42124b464dc58019250afe0ef57fd7763e boost_1_88_0_rc1.zip 3c334a9a743b68a35452b0223be8932fb39f26a6938382f9b9e625c4df99602c boost_1_88_0_rc1.tar.gz 9e42c0611500151d795d66a07ef0a21036c02d24678e2e887caf6d97fcbc25ca boost_1_88_0_rc1.tar.bz2 7faf60c4cb12ee90270e41716cf3735a8739016d7346983ce9f5e899e510b26d boost_1_88_0_rc1.7z Release notes (still need updates): https://www.boost.org/users/history/version_1_88_0.html Please try the beta and report any problems you encounter. Thanks to everyone who contributed to the release. -- Boost Release Team

1 0

boost::json question
by Keeling, William 12 Feb '25

12 Feb '25

json::value RCamCfg::GetCfgValue(const std::string& key) { try {return config_.at_pointer(key);} catch(...) { json::value x; return x;} } bool RCamCfg::SetCfgValue(const std::string& key, const json::value& val) { try {config_.set_at_pointer(key, val);} catch(...) {return false;} return {true}; } The first function compiles and runs but the second fails to compile with the following: error: 'class boost::json::value' has no member named 'set_at_pointer'; did you mean 'at_pointer'? config_is defined as "json::value config_;" Any ideas what I am doing wrong? Thanks William Keeling

3 4

Newbie - Using Boost ASIO and Boost Thread from CMake based project
by Russell Haley 11 Feb '25

11 Feb '25

Hello, I am implementing a serial port protocol in a Linux based library. We build boost ourselves (1.86.0) for inclusion in thrift so I am trying to use as much as I can just from the Boost libraries to gain some experience with them. My serial port driver is using the serial_port class from Boost ASIO. It's super cool and working well. To include Boost ASIO in my CMake target, all I have done is this: cmake_minimum_required(VERSION 3.30) set(CMAKE_CXX_STANDARD 20) set(BOOST_ROOT "${PROJECT_SOURCE_DIR}/../dataman_service/boost-install-x86_64-Debug/") find_package(Boost CONFIG) #This is an alternate use? #find_package(Boost NO_MODULE) add_library(L2PUtility L2Packet.cpp L1Transport.cpp crc1021.cpp) target_include_directories(L2PUtility PUBLIC ${CMAKE_SOURCE_DIR} ${BOOST_ROOT}/include) Note there is no target_link_libraries, but ASIO works. I thought that was because it's an HPP/Header only implementation? Since I need to add some threading to the project, I thought I would use the boost_thread library. Examples online show the inclusion of boost/thread.hpp, so I assumed it is another header only implementation and no link library is needed but I am getting a linking error: [2/4] Linking CXX executable L2PSecondary FAILED: L2PSecondary : && /usr/bin/c++ -g CMakeFiles/L2PSecondary.dir/main.cpp.o -o L2PSecondary libL2PUtility.a && : /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o): warning: relocation against `_ZTVN5boost6detail16thread_data_baseE' in read-only section `.text._ZN5boost6detail16thread_data_baseC2Ev[_ZN5boost6detail16thread_data_baseC5Ev]' /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o): in function `L1Transport::start_detached()': /home/rhaley/tuleap/BoostAsioL2p/L1Transport.cpp:440:(.text+0x1b32): undefined reference to `boost::thread::detach()' /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o): in function `boost::detail::thread_data_base::thread_data_base()': /home/rhaley/tuleap/BoostAsioL2p/../stroma_dataman_service/boost-install-x86_64-Debug/include/boost/thread/pthread/thread_data.hpp:162:(.text._ZN5boost6detail16thread_data_baseC2Ev[_ZN5boost6detail16thread_data_baseC5Ev]+0x24): undefined reference to `vtable for boost::detail::thread_data_base' /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o): in function `boost::thread::start_thread()': /home/rhaley/tuleap/BoostAsioL2p/../stroma_dataman_service/boost-install-x86_64-Debug/include/boost/thread/detail/thread.hpp:182:(.text._ZN5boost6thread12start_threadEv[_ZN5boost6thread12start_threadEv]+0x28): undefined reference to `boost::thread::start_thread_noexcept()' /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o): in function `boost::thread::~thread()': /home/rhaley/tuleap/BoostAsioL2p/../stroma_dataman_service/boost-install-x86_64-Debug/include/boost/thread/detail/thread.hpp:257:(.text._ZN5boost6threadD2Ev[_ZN5boost6threadD5Ev]+0x18): undefined reference to `boost::thread::detach()' /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o): in function `boost::thread::get_id() const': /home/rhaley/tuleap/BoostAsioL2p/../stroma_dataman_service/boost-install-x86_64-Debug/include/boost/thread/detail/thread.hpp:738:(.text._ZNK5boost6thread6get_idEv[_ZNK5boost6thread6get_idEv]+0x27): undefined reference to `boost::thread::native_handle()' /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o): in function `boost::thread::join()': /home/rhaley/tuleap/BoostAsioL2p/../stroma_dataman_service/boost-install-x86_64-Debug/include/boost/thread/detail/thread.hpp:762:(.text._ZN5boost6thread4joinEv[_ZN5boost6thread4joinEv]+0x90): undefined reference to `boost::thread::join_noexcept()' /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o): in function `boost::detail::thread_data<boost::_bi::bind_t<void, boost::_mfi::mf<void (L1Transport::*)(), void, L1Transport>, boost::_bi::list<boost::_bi::value<L1Transport*> > > >::~thread_data()': /home/rhaley/tuleap/BoostAsioL2p/../stroma_dataman_service/boost-install-x86_64-Debug/include/boost/thread/detail/thread.hpp:94:(.text._ZN5boost6detail11thread_dataINS_3_bi6bind_tIvNS_4_mfi2mfIM11L1TransportFvvEvS6_JEEENS2_4listIJNS2_5valueIPS6_EEEEEEEED2Ev[_ZN5boost6detail11thread_dataINS_3_bi6bind_tIvNS_4_mfi2mfIM11L1TransportFvvEvS6_JEEENS2_4listIJNS2_5valueIPS6_EEEEEEEED5Ev]+0x26): undefined reference to `boost::detail::thread_data_base::~thread_data_base()' /usr/bin/ld: libL2PUtility.a(L1Transport.cpp.o):(.data.rel.ro._ZTIN5boost6detail11thread_dataINS_3_bi6bind_tIvNS_4_mfi2mfIM11L1TransportFvvEvS6_JEEENS2_4listIJNS2_5valueIPS6_EEEEEEEEE[_ZTIN5boost6detail11thread_dataINS_3_bi6bind_tIvNS_4_mfi2mfIM11L1TransportFvvEvS6_JEEENS2_4listIJNS2_5valueIPS6_EEEEEEEEE]+0x10): undefined reference to `typeinfo for boost::detail::thread_data_base' /usr/bin/ld: warning: creating DT_TEXTREL in a PIE collect2: error: ld returned 1 exit status I tried adding a target_link_library: target_link_libraries(L2PUtility PUBLIC boost_thread) To no avail. I now get a missing library in the EXECUTABLE, not in the library that actually includes boost_thread! Does that mean it found it for the L2Utility library? (so confused...) Here is my executable target: add_executable(L2PSecondary main.cpp) target_include_directories(L2PSecondary PRIVATE ${CMAKE_SOURCE_DIR} ${BOOST_ROOT}/include) target_link_libraries(L2PSecondary PRIVATE L2PUtility) And here is the linking error: [1/2] Linking CXX executable L2PSecondary FAILED: L2PSecondary : && /usr/bin/c++ -g CMakeFiles/L2PSecondary.dir/main.cpp.o -o L2PSecondary libL2PUtility.a -lboost_thread && : /usr/bin/ld: cannot find -lboost_thread: No such file or directory collect2: error: ld returned 1 exit status ninja: build stopped: subcommand failed. I confirmed that my boost installation has the library libboost_tread.a. rhaley@linuxdev2:~/tuleap/dataman_service/boost-install-x86_64-Debug$ find . -iname "*thread*.a" ./lib/libboost_thread.a Adding link libraries to the executable targets doesn't fix anything. Can anyone point out what I am doing wrong? Thanks in advance, Russ

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special character handling problem
by budhirajakush7＠gmail.com 30 Jan '25

30 Jan '25

hi everyone i have a problem while passing flag with a space it gets break this is my jamroot snippet my_var = "Nov 30 2024" ; my_var2 = $(PVK_ACCESSDATE_LONG) ; ECHO "$(my_var2)" ; ECHO "$(my_var)" ; if $(PROTOCOL) = common { c_flags = $(CXXFLAGS) ; c_flags += -DPVK_ACCESSDATE_LONG="\"\\\"$(my_var2)\\\"\"" ; c_flags += -DPVK_ACCESSDATE_LONG="\"\\\$(my_var)\\\"\"" ; } both my_var and my_var2 are echoing the same thing but when passing to flags they get break here is the log Nov 30 2024 Nov 30 2024 c_flags: -DPVK_VTL_VERSION="\"24.2\"" c_flags: -DPVK_ACCESSDATE_LONG="\"Nov\"" c_flags: -DPVK_ACCESSDATE_LONG="\"30\"" c_flags: -DPVK_ACCESSDATE_LONG="\"2024\"" c_flags: -DPVK_ACCESSDATE_LONG="\Nov 30 2024\"" c_flags: -DPVK_BASE_VERSION="\"24.2\"" c_flags: Someone please help

1 0

"error: Unable to find file or target named" when using BCP to change Boost namespace
by Nicholas Williams 17 Jan '25

17 Jan '25

Background: My organization uses Boost internally for one of its software products, which is itself a C++ library. Users of our library also often use Boost. As such, we must compile our Boost in a different namespace so that the Boost symbols loaded when our library loads do not interfere with whatever different-version Boost symbols our users might load. Historically, another member of the team has been responsible for building new versions of Boost, but now it's me. I am doing this the same way our code/documentation has previously done it, but it is no longer working, and the errors I'm receiving are not familiar to the team member who was previously responsible for this. The last time we built a new Boost version was 1.80.0. I am now doing it with 1.87.0. The example: Further below, I include a lot of information and build commands, but that might not be useful to you. To help, I have created a minimal reproduction program for reproducing the error. You can clone and use it here: https://github.com/beamerblvd/unable-find-target-with-boost-bcp The good: With minimal effort and using our existing tools and configurations, I was easily able to bootstrap `b2` and then run `b2` to build stock Boost with the normal `boost` namespace. All of that worked perfectly and without error. The bad: When I went to do the same thing but with our custom namespace (via bcp), things fell apart. Our existing tooling copies the untouched 1.87.0 source tree into {dir}/_src. {dir}/user-config.jam is configured as follows: ``` constant BOOST_VERSION : mybranchname-1.87.0.a ; constant MY_PLATFORM : macos15-clang16-arm-d ; constant MY_LABEL : MYextralLabel ; constant BOOST_USER_CONFIG : <my_boost/config/user.hpp> ; using clang : 16 : clang++ : <cxxflags>-fvisibility=hidden <cxxflags>-fvisibility-inlines-hidden ; ``` Within {dir}/_src, I call `bootstrap.sh` and then build `bcp` with: bc -sBOOST_ROOT={dir}/_src \ --boost-build=tools/build/src \ cxxstd=20 \ -d \ 2 \ -j \ 2 \ -q \ --prefix={dir}/bcp \ --build-dir={dir}/bcp \ --stagedir={dir}/bcp/stage \ --user-config={dir}/user-config.jam \ --layout=system \ toolset=clang-darwin \ threading=multi \ link=shared \ architecture=arm \ instruction-set=nocona \ address-model=64 \ --without-python \ --disable-icu \ variant=release tools/bcp That takes a few minutes to complete and does so without error. Once `bcp` is built, I run it with: mkdir {dir}/_dst && \ {dir}/bcp/bin/bcp --boost={dir}/_src --namespace=boost_MYextralLabel --namespace-alias Jamroot boost boost-build.jam boostcpp.jam bootstrap.bat bootstrap.sh build status tools [insert_name_of_every_dir_in_libs] {dir}/_dst That takes a few minutes to complete and does so without error. The contents of {dir}/_dst look as I would expect them to look, with diffs against {dir}/_src reflecting the change in namespace. Once complete, I cd into {dir}/_dst, re-bootstrap, and run `b2` to compile the modified Boost: b2 -sBOOST_ROOT={dir}/_dst \ --boost-build=tools/build/src \ cxxstd=20 \ -d \ 2 \ -j \ 2 \ -q \ --prefix={dir} \ --build-dir={dir}/shobj \ --stagedir={dir}/stage \ --user-config={dir}/user-config.jam \ --layout=system \ toolset=clang-darwin \ threading=multi \ link=shared \ architecture=arm \ instruction-set=nocona \ address-model=64 \ --without-python \ --disable-icu \ variant=debug This fails quickly, here: ... - native syslog supported : yes [2] - pthread supports robust mutexes : no [2] - Boost.Regex is header-only : yes [2] error: Unable to find file or target named error: '/boost/align//boost_align' error: referred to from project at error: '{dir}/_dst/libs/atomic/build' make: *** [build] Error 1 I have tried dozens of different things over the past two days and can't remember most of them, but they didn't change the outcome, so I don't supposed they're relevant. The one thing that *did* change the outcome is that, after running `bcp` and before re-bootstrapping in {dir}/_dst, I tried deleting the {dir}/_dst/boost directory. This still failed, but it got slightly further and failed with a different (albeit extremely similar) error: ... - std_wstreambuf : no [2] - std_wstreambuf : no [3] - BOOST_COMP_GNUC >= 4.3.0 : no [2] - BOOST_COMP_GNUC >= 4.3.0 : no [4] error: Unable to find file or target named error: 'libs/thread/build//boost_MYextralLabel_thread' error: referred to from project at error: '.' make: *** [build] Error 1 I feel like I've exhausted my ability to discern what the problem is. Other than updating a handful of compiler flags (like changing cxxstd=17 to cxxstd=20), I'm doing this the same way we have (allegedly) always done it, but it's not working anymore and I don't know why. I would appreciate any guidance you can offer. Thank you, Nick

2 6

"error: No best alternative for {dir}/libs/mpi/build/boost_mpi", but the build succeeds
by Nicholas Williams 17 Jan '25

17 Jan '25

I'm building the full stock, unmodified Boost 1.87.0. I have previously built Boost 1.80.0 without issue. After bootstrapping, when running `b2` to actually build Boost, I get the following "errors": ... - has stat::st_birthtimespec : yes [5] - has fdopendir(O_NOFOLLOW) : yes [5] - has dirent::d_type : yes [5] - has POSIX *at APIs : no [5] - has fallocate : no [5] - cxx11_static_assert : yes [5] error: No best alternative for {dir}/libs/mpi/build/boost_mpi with <abi>aapcs <address-model>64 <architecture>arm <asynch-exceptions>off <binary-format>mach-o <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <boost.cobalt.executor>any_io_executor <boost.cobalt.pmr>std <context-impl>fcontext <coverage>off <cxxstd-dialect>iso <cxxstd>20 <debug-symbols>off <exception-handling>on <extern-c-nothrow>off <inlining>full <instruction-set>nocona <known-warnings>hide <link>shared <optimization>speed <os>MACOSX <pch>on <preserve-test-targets>on <profiling>off <python-debugging>off <python>3.9 <rtti>on <runtime-debugging>off <runtime-link>shared <stdlib>native <strip>off <target-os>darwin <testing.execute>on <threadapi>pthread <threading>multi <toolset-clang:platform>darwin <toolset-clang:version>14 <toolset>clang <variant>release <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <x-deduced-platform>arm_64 matched: (empty) matched: (empty) error: No best alternative for {dir}/libs/mpi/build/boost_mpi with <abi>aapcs <address-model>64 <architecture>arm <asynch-exceptions>off <binary-format>mach-o <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <boost.cobalt.executor>any_io_executor <boost.cobalt.pmr>std <coverage>off <cxxstd-dialect>iso <cxxstd>20 <debug-symbols>off <exception-handling>on <extern-c-nothrow>off <inlining>full <instruction-set>nocona <known-warnings>hide <link>shared <optimization>speed <os>MACOSX <pch>on <preserve-test-targets>on <profiling>off <python-debugging>off <python>3.9 <rtti>on <runtime-debugging>off <runtime-link>shared <stdlib>native <strip>off <target-os>darwin <testing.execute>on <threadapi>pthread <threading>multi <toolset-clang:platform>darwin <toolset-clang:version>14 <toolset>clang <variant>release <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <x-deduced-platform>arm_64 matched: (empty) matched: (empty) - gcc visibility : yes [2] - cxx14_decltype_auto : yes [2] - cxx14_generic_lambdas : yes [2] ... I used scare quotes around "errors," because these errors do not appear to actually break anything. The build completes fully and successfully, and all the libraries are built as expected. It appears to be more of a warning than an error, but I don't love warnings either, so I'd like to solve it. The only relevant result I could find Googling about this was [this other mailing list message]( https://lists.boost.org/Archives/boost/2024/11/258275.php) which was a reply to "[release] Boost 1.87.0 Beta 2 Release Candidate is available," and to which nobody ever replied. Doesn't really clear anything up for me. FWIW, I get these "errors" on RHEL 8 GCC 8, 9 GCC 11, and 9 GCC 14; Ubuntu 20.04 GCC 9, 22.04 GCC 11, and 24.04 GCC 13; macOS 12 Clang 14 (Intel and ARM), 14 Clang 16 (Intel and ARM), and 15 Clang 16 (Intel and ARM); Windows 10 MSVC 2022 and 11 MSVR 2022; and Windows Server 2022 MSVC 2022 and 2025 MSVC 2022. Any insights or guidance would be appreciated. Thanks, Nick

2 4

ICU not found while building Boost
by Cory Riddell 13 Jan '25

13 Jan '25

I'm having trouble building Boost 1.87 on Windows using the latest VS2022. I'm starting from the "x64 Native Tools Command Prompt for VS 2022". I've downloaded the latest ICU binaries and updated my PATH, LIB, and INCLUDE environment variables: set PATH=%PATH%;D:\icu\bin64 set LIB=%LIB%;D:\icu\lib64 set INCLUDE=%INCLUDE%;D:\icu\include I go into my boost directory and run bootstrap.bat. It seems to complete, creating b2.exe. I then run "b2 address-model=64" and it's not finding icu: E:\boost_1_87_0>b2 address-model=64 Performing configuration checks - default address-model : 64-bit [1] - default architecture : x86 [1] Building the Boost C++ Libraries. warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam. note: to suppress this message, pass "--without-graph_parallel" to bjam. - icu : no [2] - iconv (libc) : no [2] - iconv (separate) : no [2] - cxx11_auto_declarations : yes [2] - cxx11_decltype : yes [2] I ctrl-c to quit at this point and looked at my config.log and it doesn't seem to find icu when building has_icu_test.obj: compile-c-c++ bin.v2\libs\locale\build\msvc-14.3\debug\x86_64\link-static\threading-multi\has_icu_test.obj has_icu_test.cpp E:\boost_1_87_0\libs\locale\build\has_icu_test.cpp(6): fatal error C1083: Cannot open include file: 'unicode/coll.h': No such file or directory The file D:\icu\include\unicode\coll.h does exist though. Is there some reason my environment variables don't make it to the processes kicked off by b2? Or am I overlooking something obvious? Any help is greatly appreciated. Cory

3 3

Generating a fully namespaced boost installation
by Janosch Machowinski 07 Jan '25

07 Jan '25

Hi, we ran into an issue, were the system installation of boost is exposed by a third party lib we rely on (ROS), but it contains a bug. The bug in boost is fixed in a way more recent version of boost, therefore we are looking into using two versions of boost at the same time. To archive this, we want to run the newer boost version in a custom namespace, and already found the bcp tool, that helps with generating a namespace version of boost for us. The issue we are now hitting is, that the includes in our custom boost version are not altered by bcp, and therefore pick up the system headers. E.g. geometry.hpp contains '#include <boost/geometry/geometry.hpp>' but in order to work for us, it would need to be '#include <our_boost/geometry/geometry.hpp>'. Are we missing some magical bcp option, or is this just not supported ? Thx Janosch -- Janosch Machowinski cellumation GmbH | Linzer Str.5 | 28359 Bremen | Germany P: +49 421 331135 35 F: +49 421 331135 99 J.Machowinski(a)cellumation.com Website | YouTube Registernummer: HRB32569 | Registergericht: Amtsgericht Bremen | Ust-Id.Nr.: DE313140406 Geschäftsführer: Dr.-Ing. Hendrik Thamer, Claudio Uriarte Diese E-Mail und alle damit übermittelten Dateien sind vertraulich und ausschließlich für die Verwendung durch die Person oder Gesellschaft, an die sie adressiert sind, bestimmt. Die Weitergabe sowie Vervielfältigung, Verwertung und Mitteilung des Inhalts der E-Mail sind nur mit unserer ausdrücklichen Genehmigung gestattet. Alle Rechte vorbehalten, insbesondere für den Fall der Schutzrechtsanmeldung This e-mail and all files transmitted with it are confidential and intended exclusively for use by the person or company to whom they are addressed. The transmission, reproduction, exploitation and communication of the contents of the e-mail are only permitted with our express permission. All rights reserved, in particular in the event of an application for industrial property rights.

1 0

asio::strand: Order of execution
by Georg Gast 28 Dec '24

28 Dec '24

Hi, If I use a asio::strand and post() there multiple function objects, are they executed in the same order or is the order of execution not specified? I think to use it as a work queue but I need them to be processed in sequence... Thx Georg

1 0

[release] Boost 1.87.0
by Marshall Clow 12 Dec '24

12 Dec '24

Release 1.87.0 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 two new libraries: * Boost.Parser: A framework for building parsers, from Zach Laine. The release also contains numerous enhancements and bug fixes for existing libraries. For details, including download links, see <http://www.boost.org/users/news/version_1.87.0> You can also download directly from: <https://boostorg.jfrog.io/artifactory/main/release/1.87.0/> 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. -- The Boost Release Team Marshall Clow, Glen Fernandes, Ion Gaztañaga

1 0

[release] Boost 1.87.0 beta 1 released
by Marshall Clow 16 Nov '24

16 Nov '24

Boost release 1.86.0 beta 1 is now available at: https://archives.boost.io/beta/1.87.0.beta1/source/ The SHA256 checksums are: 2e7cdf358526e8937b36b93fc96c501b8d6a0c8436e95e65440de31c48ec3086 boost_1_87_0_b1.tar.bz2 98a86940c13509dfd0288a3075280f46a76c9a3faeb8a9bf49ca7f9e6a271995 boost_1_87_0_b1.tar.gz 2ca4c019d0c96fd160dec5292a7a6bfcf7b4e592cd238a2207e17084f8021d08 boost_1_87_0_b1.zip 5ea32facd963dbb79ceb5bda7ef7546017ea5da854158f8933bbad74d6bbe622 boost_1_87_0_b1.7z This is slightly different than the RC3. Someone committed a documentation fix to master after we had started the release process, and rather than re-do the whole thing (and re-tag everything), we decided to go with the release that we prepared. The person who did this has been informed of the problems that he caused, and I don’t think he’ll do it again. Release notes (still need updates): https://www.boost.org/users/history/version_1_87_x.html Please try the beta and report any problems you encounter. Thanks to everyone who contributed to the release. -- Boost Release Team

1 0

Unable to find boost atomic library header files//boost-1.84.0
by Pawan Badganchi 15 Oct '24

15 Oct '24

Hi, I am trying to resolve below error. Tried adding below path to atomic.cmake custom file but still failing with same issue. Could you please help here? include_directories( ${Boost_LIBRARY_DIRS}/atomic/test ) ERROR: Compilation failed Stdout: [ 50%] Building CXX object CMakeFiles/test_atomic.dir/atomicity.cpp.o Stderr: /sdk/sysroots/core2-64-poky-linux/usr/share/doc/boost-atomic/examples**/atomicity.cpp:38:10: fatal error: test_clock.hpp: No such file or directory 38 | #include "test_clock.hpp" | ^~~~~~~~~~~~~~~~ compilation terminated. make[2]: ***** [CMakeFiles/test_atomic.dir/build.make:76: CMakeFiles/test_atomic.dir/atomicity.cpp.o] Error 1 make[1]: *** [CMakeFiles/Makefile2:83: CMakeFiles/test_atomic.dir/all] Error 2 make: *** [Makefile:91: all] Error 2 Returncode: Expected: 0 Actual: 2 Below is the my atomic.cmake file content. cmake_minimum_required(VERSION 2.8) FIND_PACKAGE(Boost REQUIRED COMPONENTS atomic ) FIND_PACKAGE(Boost REQUIRED COMPONENTS thread ) include_directories( ${Boost_LIBRARY_DIRS}/atomic/test ) add_executable(test_atomic atomicity.cpp ) target_link_libraries(test_atomic ${Boost_LIBRARIES} ) Thanks & Regards, Pawan KPIT Technologies,Pune This message contains information that may be privileged or confidential and is the property of the KPIT Technologies Ltd. It is intended only for the person to whom it is addressed. If you are not the intended recipient, you are not authorized to read, print, retain copy, disseminate, distribute, or use this message or any part thereof. If you receive this message in error, please notify the sender immediately and delete all copies of this message. KPIT Technologies Ltd. does not accept any liability for virus infected mails.

1 0

[boost] Boost.LEAF in Embedded Systems (CppCon)
by Vinnie Falco 23 Sep '24

23 Sep '24

At CppCon 2024 the C++ Alliance sponsored a program to interview conference goers about Boost-related topics. This is the first video in the series: Boost.LEAF in Embedded Systems: Insights from Ex-Google Engineer Khalil Estelle at CppCon https://www.youtube.com/shorts/BksBxnTLltY Enjoy! Thanks

1 0

[PFR] names_as_array doesn't work for structs with array fields
by Chinmay Dalal 23 Sep '24

23 Sep '24

Hi, `boost::pfr::names_as_array<T>()` does not compile if `T` has an array member. Someone commented a fix on a similar issue: https://github.com/boostorg/pfr/issues/170 What would be the appropriate place to ask for including this fix? Background: I'm trying to print structs as CSV. I came up with this: https://paste.sr.ht/~p00f/667e013c23c991ddec91e9cdaa00bd3c11cb2ceb But as soon as I include an array member: https://paste.sr.ht/~p00f/aa08531cd100f8b94c49ead2c541ff96f55b362e it does not compile: https://paste.sr.ht/~p00f/636c1e3ab4f5ba86aa865f70f32337b3d2872047 Thanks, Chinmay

1 0

Boost.Asio UDP sockets guarantee for ordering
by Kalesis, Ioannis 18 Sep '24

18 Sep '24

Hello, I am using boost.asio for udp sockets to broadcast multicast traffic. For that, I am using async_send methods. I am aware that there is no guarantee for the order of the completion handlers for the async_send calls, and for that reason I have implemented a queueing mechanism, where the coroutine waits for the current async_send to complete before moving forward to the next call. However, given the low latency requirement of the application, I believe that the following approach may be more optimal: * The async_send operation would happen immediately one after another (not concurrently) without waiting for the previous ones to complete. * The queueing mechanism would be used but only for the post processing work completion handlers. The above will provide both better latency (by sending the packets sooner instead of having to enqeue/spawn_co/dequeue) and still maintain the strict ordering requirement of the post processing work. However, one concern that I have with this approach is with the "multiple" async_send calls being made one after the other. After searching on this topic, I arrived at the conclusion that this is "safe" given that they are not composed operations so there is no risk that the data will be interleaved between packets. The point that I need help understanding is whether there is a guarantee on the order of the packets being enqueued to kernels network stack. For the following example: ``` udp_socket.async_send(packet1,...); upd_socket.async_send(packet2,...); ``` Is there any possible way for "packet2" to be enqueued 1st in the kernel network stack? Similarly, Is it possible for it to be sent by the OS 1st? I acknowledge that even if everything went perfect on the machine, packets could still be received out-of-order to the clients and that is acceptable, however I would like at least to not have the application contribute to this as part of a software issue. The application has multiple threads that run the same io_context with strands in place to have thread-safety. My machine is a redhat 9, gcc 11.4 Thank you in advance for your time and cooperation. Best regards

4 4

Re: [Boost-users] Boost-users Digest, Vol 5734, Issue 1
by Oran Johnson 09 Sep '24

09 Sep '24

Any ideas as to how to correct the following? johnson@fedora:~/opensource$ svn co https://svn.boost.org/svn/boost/sandbox sandbox svn: E170013: Unable to connect to a repository at URL 'https://svn.boost.org/svn/boost/sandbox' svn: E000111: Error running context: Connection refused ________________________________ From: Boost-users <boost-users-bounces(a)lists.boost.org> on behalf of boost-users-request(a)lists.boost.org <boost-users-request(a)lists.boost.org> Sent: Tuesday, August 27, 2024 8:00 AM To: boost-users(a)lists.boost.org <boost-users(a)lists.boost.org> Subject: Boost-users Digest, Vol 5734, Issue 1 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. Accessing the Boost Sandbox (oranjsr(a)gmail.com) ---------------------------------------------------------------------- Message: 1 Date: Mon, 26 Aug 2024 10:00:58 -0400 From: <oranjsr(a)gmail.com> To: <boost-users(a)lists.boost.org> Subject: [Boost-users] Accessing the Boost Sandbox Message-ID: <010601daf7c0$60c585b0$22509110$(a)gmail.com> Content-Type: text/plain; charset="utf-8" Hi, I'm looking at a source forge project with the following required libraries: 1) Boost version 1.39 or later 2) TBB (Threading Building Blocks) version 2.1 or later 3) MSM (Meta State Machine) version 1.2 or later 4) Boost Logging Library v2 #3 appears to be in the boost sandbox Does boost sandbox still exists? Boost Sandbox When boost was developed using subversion, the Boost Sandbox contained unreviewed code that is intended to eventually become a part of the Boost libraries. New libraries should be developed separately as <https://svn.boost.org/trac/boost/wiki/ModularBoost> git modules, and existing projects should be <https://svn.boost.org/trac/boost/wiki/ExtractSandbox> moved to GitHub. The sandbox remains as a historical record. Accessing the Boost Sandbox The Boost Sandbox lives at <https://svn.boost.org/svn/boost/sandbox> https://svn.boost.org/svn/boost/sandbox within the old Boost Subversion repository. Regards Oran

2 1

[filesystem] why is this file not found?
by Michael Burr 04 Sep '24

04 Sep '24

I'm having difficulty using boost/filesystem.hpp on a simple test example. If I understand things correctly, this code should see if it can find the files called "test_file" and "test_file2" in the current directory. ``` #include <boost/filesystem.hpp> #include <iostream> using namespace boost::filesystem; int main() { path file1 = "test_file", file2 = "test_file2"; if(status(file1).type() == file_not_found) std::cout << "First file not found\n"; if(status(file2).type() == file_not_found) std::cout << "Second file not found\n"; return 0; } ``` If I run the following, ``` touch test_file g++ filesystem_check.cpp -lboost_filesystem ./a.out ``` the result is > First file not found > Second file not found I expected only the second file to be not found. I arrived at this question because exists(file1) was returning false when I thought it should return true, and I traced the issue back to this check. I've also tried this example with an absolute path, and the results were the same. This is using Boost 1.81 installed via macports on a mac with OS 12.5.1 (so slightly out-of-date OS). Is this a mac issue or am I missing something in my code?

2 1

Accessing the Boost Sandbox
by oranjsr＠gmail.com 26 Aug '24

26 Aug '24

Hi, I'm looking at a source forge project with the following required libraries: 1) Boost version 1.39 or later 2) TBB (Threading Building Blocks) version 2.1 or later 3) MSM (Meta State Machine) version 1.2 or later 4) Boost Logging Library v2 #3 appears to be in the boost sandbox Does boost sandbox still exists? Boost Sandbox When boost was developed using subversion, the Boost Sandbox contained unreviewed code that is intended to eventually become a part of the Boost libraries. New libraries should be developed separately as <https://svn.boost.org/trac/boost/wiki/ModularBoost> git modules, and existing projects should be <https://svn.boost.org/trac/boost/wiki/ExtractSandbox> moved to GitHub. The sandbox remains as a historical record. Accessing the Boost Sandbox The Boost Sandbox lives at <https://svn.boost.org/svn/boost/sandbox> https://svn.boost.org/svn/boost/sandbox within the old Boost Subversion repository. Regards Oran

1 0

Code using Boost::Compute builds fine on Linux, but not on Windows
by David Frischknecht 22 Aug '24

22 Aug '24

I wrote this simple program to learn how to use Boost::Compute. The program failed to build on Windows, but builds without any errors on Linux. If I modify the program to only operate on one vector, it works fine. On Windows I'm using vcpkg to pull in both Boost::Compute as well as the OpenCL SDK and I'm using Visual Studio 2022 to build the project. #define CL_TARGET_OPENCL_VERSION 300 #include <random> #include <vector> #include <boost/compute/core.hpp> #include <boost/compute/lambda.hpp> #include <boost/compute/algorithm/transform.hpp> #include <boost/compute/container/vector.hpp> std::mt19937 rng{ std::random_device()() }; std::uniform_int_distribution<> dist(1); namespace compute = boost::compute; using namespace boost::compute::lambda; int GetRandomNumber() { return dist(rng); } int main(int argc, char* argv[]) { const auto device = compute::system::default_device(); const compute::context context(device); compute::command_queue commandQueue(context, device); std::vector<int> hostVector1(10000); std::vector<int> hostVector2(10000); std::vector<int> hostResultVector(10000); std::ranges::generate(hostVector1, GetRandomNumber); std::ranges::generate(hostVector2, GetRandomNumber); compute::vector<int> deviceVector1(hostVector1.size(), context); compute::vector<int> deviceVector2(hostVector2.size(), context); compute::vector<int> deviceResultVector(hostResultVector.size(), context); compute::copy(hostVector1.begin(), hostVector1.end(), deviceVector1.begin(), commandQueue); compute::copy(hostVector2.begin(), hostVector2.end(), deviceVector2.begin(), commandQueue); transform(deviceVector1.begin(), deviceVector1.end(), deviceVector2.begin(), deviceResultVector.begin(), _1 + _2, commandQueue); compute::copy(deviceResultVector.begin(), deviceResultVector.end(), hostResultVector.begin(), commandQueue); return 0; } Here is the build output: Build started at 11:13 PM... 1>------ Build started: Project: BoostComputeTest, Configuration: Debug x64 ------ 1>Main.cpp 1>C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\transform_iterator.hpp(177,53): error C2039: 'get_buffer': is not a member of 'boost::compute::zip_iterator<boost::tuples::tuple<boost::compute::buffer_iterator<T>,boost::compute::buffer_iterator<T>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>' 1>C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\transform_iterator.hpp(177,53): error C2039: with 1>C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\transform_iterator.hpp(177,53): error C2039: [ 1>C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\transform_iterator.hpp(177,53): error C2039: T=int 1>C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\transform_iterator.hpp(177,53): error C2039: ] 1>(compiling source file 'Main.cpp') 1> C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\zip_iterator.hpp(172,7): 1> see declaration of 'boost::compute::zip_iterator<boost::tuples::tuple<boost::compute::buffer_iterator<T>,boost::compute::buffer_iterator<T>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>' 1> with 1> [ 1> T=int 1> ] 1> C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\transform_iterator.hpp(177,53): 1> the template instantiation context (the oldest one first) is 1> C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\Main.cpp(40,2): 1> see reference to function template instantiation 'OutputIterator boost::compute::transform<boost::compute::buffer_iterator<T>,boost::compute::buffer_iterator<T>,boost::compute::buffer_iterator<T>,boost::compute::lambda::expression<Expr>>(InputIterator1,InputIterator1,InputIterator2,OutputIterator,BinaryOperator,boost::compute::command_queue &)' being compiled 1> with 1> [ 1> OutputIterator=boost::compute::buffer_iterator<int>, 1> T=int, 1> Expr=boost::proto::exprns_::basic_expr<boost::proto::tagns_::tag::plus,boost::proto::argsns_::list2<const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<0>>,0>> &,const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<1>>,0>> &>,2>, 1> InputIterator1=boost::compute::buffer_iterator<int>, 1> InputIterator2=boost::compute::buffer_iterator<int>, 1> BinaryOperator=boost::compute::lambda::expression<boost::proto::exprns_::basic_expr<boost::proto::tagns_::tag::plus,boost::proto::argsns_::list2<const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<0>>,0>> &,const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<1>>,0>> &>,2>> 1> ] 1> C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\algorithm\transform.hpp(75,12): 1> see reference to function template instantiation 'OutputIterator boost::compute::transform<boost::compute::zip_iterator<boost::tuples::tuple<boost::compute::buffer_iterator<T>,boost::compute::buffer_iterator<T>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>,OutputIterator,boost::compute::detail::unpacked<BinaryOperator>>(InputIterator,InputIterator,OutputIterator,UnaryOperator,boost::compute::command_queue &)' being compiled 1> with 1> [ 1> OutputIterator=boost::compute::buffer_iterator<int>, 1> T=int, 1> BinaryOperator=boost::compute::lambda::expression<boost::proto::exprns_::basic_expr<boost::proto::tagns_::tag::plus,boost::proto::argsns_::list2<const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<0>>,0>> &,const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<1>>,0>> &>,2>>, 1> InputIterator=boost::compute::zip_iterator<boost::tuples::tuple<boost::compute::buffer_iterator<int>,boost::compute::buffer_iterator<int>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>, 1> UnaryOperator=boost::compute::detail::unpacked<boost::compute::lambda::expression<boost::proto::exprns_::basic_expr<boost::proto::tagns_::tag::plus,boost::proto::argsns_::list2<const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<0>>,0>> &,const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<1>>,0>> &>,2>>> 1> ] 1> C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\algorithm\transform.hpp(48,34): 1> see reference to class template instantiation 'boost::compute::transform_iterator<InputIterator,UnaryOperator>' being compiled 1> with 1> [ 1> InputIterator=boost::compute::zip_iterator<boost::tuples::tuple<boost::compute::buffer_iterator<int>,boost::compute::buffer_iterator<int>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>, 1> UnaryOperator=boost::compute::detail::unpacked<boost::compute::lambda::expression<boost::proto::exprns_::basic_expr<boost::proto::tagns_::tag::plus,boost::proto::argsns_::list2<const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<0>>,0>> &,const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<1>>,0>> &>,2>>> 1> ] 1> C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\transform_iterator.hpp(175,15): 1> while compiling class template member function 'int boost::compute::transform_iterator<InputIterator,UnaryOperator>::dereference(void) const' 1> with 1> [ 1> InputIterator=boost::compute::zip_iterator<boost::tuples::tuple<boost::compute::buffer_iterator<int>,boost::compute::buffer_iterator<int>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>, 1> UnaryOperator=boost::compute::detail::unpacked<boost::compute::lambda::expression<boost::proto::exprns_::basic_expr<boost::proto::tagns_::tag::plus,boost::proto::argsns_::list2<const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<0>>,0>> &,const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<1>>,0>> &>,2>>> 1> ] 1> C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\iterator\iterator_facade.hpp(631,11): 1> see the first reference to 'boost::compute::transform_iterator<InputIterator,UnaryOperator>::dereference' in 'boost::iterators::iterator_core_access::dereference' 1> with 1> [ 1> InputIterator=boost::compute::zip_iterator<boost::tuples::tuple<boost::compute::buffer_iterator<int>,boost::compute::buffer_iterator<int>,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type>>, 1> UnaryOperator=boost::compute::detail::unpacked<boost::compute::lambda::expression<boost::proto::exprns_::basic_expr<boost::proto::tagns_::tag::plus,boost::proto::argsns_::list2<const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<0>>,0>> &,const boost::compute::lambda::expression<boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::proto::argsns_::term<boost::compute::lambda::placeholder<1>>,0>> &>,2>>> 1> ] 1>C:\Users\Dave\source\repos\BoostComputeTest\BoostComputeTest\vcpkg_installed\x64-windows\x64-windows\include\boost\compute\iterator\transform_iterator.hpp(177,32): error C2530: 'context': references must be initialized 1>(compiling source file 'Main.cpp') 1>Done building project "BoostComputeTest.vcxproj" -- FAILED. ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== ========== Build completed at 11:13 PM and took 03.315 seconds ========== Is there something I'm missing from my project configuration on Windows? Thanks, Dave F.

1 0

Abwesenheitsnachricht: Re: [boost] [release] Boost.1.86.0
by Sören Textor 16 Aug '24

16 Aug '24

Derzeit bin ich nicht im Hause Ihre E-Mail wird nicht weitergeleitet. In dringenden Fällen bitte support(a)ditec-gmbh.de oder Telefonhotline +49-6221-31698-110 oder die Zentrale +49-6221-31698-0 kontaktieren. Mit freundlichen Grüßen Dr. Sören Textor ----------------------------------------------- DiTEC Dr. Siegfried Kahlich & Dierk Langer GmbH Im Breitspiel 19 | 69126 Heidelberg | Germany Handelsregister | Mannheim | HRB 341229 Dieses Dokument ist vertraulich zu behandeln. Die Weitergabe, sowie Vervielfältigung, Verwertung und Mitteilung seines Inhalts ist nur mit unserer ausdrücklichen Genehmigung gestattet. Alle Rechte vorbehalten, insbesondere für den Fall der Schutzrechtsanmeldung. This document has to be treated confidentially. Its contents are not to be passed on, duplicated, exploited or disclosed without our express permission. All rights reserved, especially the right to apply for protective rights.

1 0

[release] Boost.1.86.0
by Marshall Clow 16 Aug '24

16 Aug '24

Release 1.86.0 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. The release contains numerous enhancements and bug fixes for existing libraries. For details, including download links, see <http://www.boost.org/users/news/version_1.86.0> You can also download directly from: <https://archives.boost.io/release/1.86.0/source/> 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. -- The Boost Release Team Marshall Clow, Glen Fernandes, Ion Ion Gaztañaga

5 5

Boost in CUDA C++
by wickedPlatypus 12 Aug '24

12 Aug '24

Hi everyone: I have been using Boost for a couple of months in Ubuntu but I have moved into Windows 11 where I am using Microsoft VIsual Studio Community. I have been trying to run a simple code using the CUDA nvcc compiler but I am getting the next errors: [cid:09f3ea52-8ad8-4931-a32b-f178768de741] [cid:afc5117d-edf1-4262-be42-601516a4123d] I want to highlight that the code is working properly in C++. I have tested this code with the next configurations: -C++14 or C++17 or C++20 -CUDA ToolKit 12.5 or 12.6 -NVIDIA driver 560.81 -Microsoft VIsual Studio Community 2022 17.10.5 The first error message is related to the use of a compiler prior to C++ 20 but even using C++ 20 the error message is still present. Also, I have attached the code to this email. I really appreciate your expertise in this issue. Thank you so much in advance to all of you!!!

2 1

Program_Options library multitoken() question
by Keeling, William 06 Aug '24

06 Aug '24

Can the number of tokens be limited/validated? I am currently raising exception in notifier() function; if that is the only way, can the option name be known in the notifier function to improve my error message? Thanks William

1 0

undefined type on vs2008 but not vs2010
by Daniel 01 Aug '24

01 Aug '24

Hi, I'm new to C++, working on an old project using the vs2008 toolset. I need to add some networking and so I started with the docs tutorial "An asynchronous TCP daytime server". Boost 1.68 Error C2027 use of undefined type 'boost::_bi::add_cref<Pm,I>' BoostAsio d:\downloads\boost_1_68_0\boost\bind\bind.hpp 2323 namespace _bi {template< class Pm, int I > struct add_cref; ... template<class Pm, class A1> struct dm_result { typedef typename add_cref< Pm, 1 >::type type; <<< 2323 }; Do I need to provide more details? Thanks

2 1

[release] Boost 1.86.0 beta 1 released
by Marshall Clow 26 Jul '24

26 Jul '24

Boost release 1.86.0 beta 1 is now available at: https://boostorg.jfrog.io/artifactory/main/beta/1.86.0.beta1/source/ The SHA256 checksums are: 6c3b6b6b1760090ebd658b764c9006d9579df2a20763ede356e059fe52989277 boost_1_86_0_b1.tar.bz2 cc0e5c0fb54ea8762c2eb9fbfd185cb8ccbe1ad33c218883f9438dbe2f9a795b boost_1_86_0_b1.zip cad677f5b746bd83c68131766554b56ebf40eb7ba94823526b03820db9dbc049 boost_1_86_0_b1.7z 82b59c0ca4d3b8bbf910ffdbbf535ef738fa1d648b8ba6f2608b516a58f89c55 boost_1_86_0_b1.tar.gz Release notes (still need updates): https://www.boost.org/users/history/version_1_86_0.html Please try the beta and report any problems you encounter. Thanks to everyone who contributed to the release. Thanks especially to Sam Darwin for his help with the tools, and figuring out what happend with RC3. -- Boost Release Team

1 0

error: template argument for template type parameter must be a type template< class Allocator = std::allocator< none > >
by Phil Phil 05 Jul '24

05 Jul '24

Greetings, I try to port a c++ project to a new environment with clang++-17, libcxx 17 and std=c++17 for x64 Linux. Also, I switched form boost 1.65 to 1.84. Now I start getting errors in boost itself: /workspace/usr/include/boost/statechart/fifo_worker.hpp:55:45: error: template argument for template type parameter must be a type 55 | template< class Allocator = std::allocator< none > > As far as I know this has to do with deprecation of some variable type in allocator. Any ideas how I might fix this on short notice? Regards

2 2

directory_iterator UNC path
by Lars Sunde 04 Jul '24

04 Jul '24

Hello, Using boost::filesystem::directory_iterator with an UNC path failed with Boost 1.84 and Windows 10. Did some research on this topic and found this bug report from 2022; https://github.com/boostorg/filesystem/issues/245 This issue contain a link to this fix; https://github.com/boostorg/filesystem/commit/9c9d127bddc2b72187c57f4933c49… When looking at boost 1.84 and 1.85 source code I cannot find the fix shown above. Please excuse my ignorance but what is the relationship between https://github.com/boostorg/filesystem and the sw released at https://www.boost.org<https://www.boost.org/> ? Kind regards, Lars [https://opengraph.githubassets.com/d5334b4df3942668241ead9dde0a136ddc1b0979…]<https://github.com/boostorg/filesystem> GitHub - boostorg/filesystem: Boost.org filesystem module<https://github.com/boostorg/filesystem> Boost.org filesystem module. Contribute to boostorg/filesystem development by creating an account on GitHub. github.com

2 2

Re: [Boost-users] Windows binaries, etc
by Michael Powell 30 Jun '24

30 Jun '24

Hello, Been a minute since I last updated my Boost libraries. Curious what the condition of the binaries is, re: VS2022 C++ compiler compatibility, alignment with current lang standards, such as this? https://boost.teeks99.com/bin/1.85.0/ As far as integration goes, I just add include and library paths to my projects, and on from there. Already more or less familiar with that aspect. Cheers, best, Michael W. Powell

2 1

boost-python - call c++ methods within another method with embedded Python ?
by Nicholas Yue 28 Jun '24

28 Jun '24

Hi I am trying to add an ability to allow for the calling of methods within a another method that is running an embedded python but I get an error saying "TypeError: No Python class registered for C++ class MyClass". #include <boost/python.hpp> class MyClass { public: MyClass() = default; void method1(); void method2(); void executePython(); }; #include <iostream> void MyClass::method1() { std::cout << "Method 1 called" << std::endl; } void MyClass::method2() { std::cout << "Method 2 called" << std::endl; } void MyClass::executePython() { try { Py_Initialize(); // Expose the current instance (self) to the embedded Python script boost::python::object main_namespace; main_namespace["self"] = boost::python::ptr(this); // Execute Python code that calls method1 and method2 on self boost::python::exec("self.method1()\nself.method2()", main_namespace); Py_Finalize(); } catch (boost::python::error_already_set&) { PyErr_Print(); } } int main() { MyClass mc; mc.executePython(); return 0; } -- Nicholas Yue https://www.linkedin.com/in/nicholasyue/

1 0

Fwd: [beast] Trying to Integrate Chunked Encoding into server-sync Example
by Max D 29 May '24

29 May '24

Hi everyone, I'm trying to integrate the manual chunked encoding example [0] into the sync-server example [1] and have difficulties understanding a compiler error. I thought I might find some help in this mailing list. Here's my diff to the original example: @@ -151,6 +151,22 @@ handle_request( req.method() != http::verb::head) return send(bad_request("Unknown HTTP-method")); + if (req.target().find("/chunked") == 0) { + std::vector<uint8_t> data; + for (int i = 0; i < 10; i++) { + data.push_back(0x00); + } + net::const_buffer buf {data.data(), 10}; + + send.send_chunk_headers(); + + for (int i = 0; i < 3; i++) { + send.send_chunk(buf); + } + + send.send_last_chunk(); + } + // Request path must be absolute and not contain "..". if( req.target().empty() || req.target()[0] != '/' || @@ -243,6 +259,29 @@ struct send_lambda http::serializer<isRequest, Body, Fields> sr{msg}; http::write(stream_, sr, ec_); } + + void + send_chunk_headers() + { + http::response<http::empty_body> res {http::status::ok, 11}; + res.set(http::field::server, "Beast"); + res.chunked(true); + + http::response_serializer<http::empty_body> sr{res}; + http::write_header(stream_, sr); + } + + void + send_last_chunk() + { + http::write(stream_, http::make_chunk_last()); + } + + void + send_chunk(net::const_buffer buf) const + { + http::write(stream_, http::make_chunk(buf)); + } }; // Handles an HTTP server connection I'm passing a TCP socket as well as the result of http::make_chunk() with a net::const_buffer to http::write() which, if I understand correctly, is the same thing that is done in the example. However, I'm getting the following error when compiling: .../server-sync/src/beast.cpp: In instantiation of ‘void send_lambda<Stream>::send_chunk(boost::asio::const_buffer) const [with Stream = boost::asio::basic_stream_socket<boost::asio::ip::tcp>]’: .../server-sync/src/beast.cpp:164:28: required from ‘void handle_request(boost::beast::string_view, boost::beast::http::request<Body, boost::beast::http::basic_fields<Allocator> >&&, Send&&) [with B ody = boost::beast::http::basic_string_body<char>; Allocator = std::allocator<char>; Send = send_lambda<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >&; boost::beast::string_view = boost::basic_string_view<char, std::char_traits< char> >; boost::beast::http::request<Body, boost::beast::http::basic_fields<Allocator> > = boost::beast::http::message<true, boost::beast::http::basic_string_body<char>, boost::beast::http::basic_fields<std::allocator<char> > >]’ .../server-sync/src/beast.cpp:313:57: required from here .../server-sync/src/beast.cpp:283:20: error: no matching function for call to ‘write(boost::asio::basic_stream_socket<boost::asio::ip::tcp>&, boost::beast::http::chunk_body<boost::asio::const_buffer>) ’ 283 | http::write(stream_, http::make_chunk(buf)); | ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The same thing happens for the send_last_chunk() call. Why isn't the call to write() working? Did I misunderstand something in the example? I'm using boost 1.71 and am compiling with GCC 10.3.0. Let me know if you need any more details. Thanks in advance for any help Max --- [0] https://www.boost.org/doc/libs/1_71_0/libs/beast/doc/html/beast/using_http/… [1] https://www.boost.org/doc/libs/1_71_0/libs/beast/example/http/server/sync/h…

2 1

boost::flyweights::intermodule_holder
by Foelsche, Peter 10 May '24

10 May '24

Dear All, Thanks for the boost library! Apparently the boost::flyweight::intermodule_holder on LINUX is creating shared memory objects, which by accident (crash?) can persist after the process having created them is already gone. As a result I ran into the following situation: I could not successfully run some code, as it attempted to create an already existing shared memory object created by another user. Would the following be a solution to this problem: Use a copy of the code of the static_holder inside another namespace as attached and compile one module with __INCLUDE_HOLDER__ defined and all the rest without this define? Peter

4 4

Boost Graph - adjacency_list in_edge_iterator are only input_iterator_tag?
by Nic 10 May '24

10 May '24

Hi, Hopefully this is the right place for this. This with Boost 1.81.0 It looks like boost::adjacency_list's in_edge_iterator, out_edge_iterator, and for bidirectional graphs also edge_iterator all are only input iterators. This seems a bit restrictive, and is regardless of the type of EdgeList template parameter. For example, this code (which seems a relatively reasonable thing to want to do) doesn't work: https://godbolt.org/z/n3PdEYo49 It doesn't work because transform_view doesn't define iterator_category if the iterator is not at least a forward iterator (I'm a bit confused as to why that is, but that's not a boost-related thing). I did some digging and found out why the iterator is always an input iterator: The iterators are defined as following: template < class BaseIter, class VertexDescriptor, class EdgeDescriptor, class Difference > struct in_edge_iter : iterator_adaptor< in_edge_iter< BaseIter, VertexDescriptor, EdgeDescriptor, Difference >, BaseIter, EdgeDescriptor, use_default, EdgeDescriptor, Difference > { // .... }; EdgeDescriptor is passed in as the reference type, but it is not a reference so the iterator adaptor always chooses input_iterator_tag for the iterator_category. Does anyone know of a workaround, or know if this is the desired behavior for edge iterators? Am I missing something obvious here? Thank you very much, Nicolas Morales

2 1

boost.asio: random_access_file, io_uring and thread safety
by Matwey V. Kornilov 30 Apr '24

30 Apr '24

Hello, random_access_file is backed by the io_uring kernel interface on Linux. However, It is still unclear from Boost.Asio documentation, whether simultaneous parallel async_write_at in-flight requests are permitted by Asio? The queue of simultaneous requests is natively supported by io_uring. Is it still true for Asio? Is it also safe to fire parallel async_write_at from different threads? -- With best regards, Matwey V. Kornilov

1 0

Is there a buffered tcp stream in ASIO?
by accelerator0099 29 Apr '24

29 Apr '24

|Prepare a tcp server listening on [::]:23380, run the following code: #include <boost/asio.hpp> namespace io = boost::asio; using boost::system::system_error; int main() { try { io::io_context ctx; using io::ip::tcp; using io::buffer; tcp::socket s1(ctx); s1.connect(tcp::endpoint(io::ip::address_v4::loopback(), 23380)); for (size_t i{}; i != 10; ++i) io::write(s1, buffer("123", 3)); } catch (system_error& e) { return 1; } } strace says there are 10 syscalls: connect(6, {sa_family=AF_INET, sin_port=htons(23380), sin_addr=inet_addr("127.0.0.1")}, 16) = 0 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 sendto(6, "123", 3, MSG_NOSIGNAL, NULL, 0) = 3 If I use boost::asio::ip::tcp::iostream: #include <boost/asio.hpp> namespace io = boost::asio; using boost::system::system_error; int main() { try { io::io_context ctx; using io::ip::tcp; using io::buffer; tcp::iostream s1{ tcp::socket(ctx) }; auto& nl = s1.socket(); nl.connect(tcp::endpoint(io::ip::address_v4::loopback(), 23380)); for (size_t i{}; i != 10; ++i) s1.write("123", 3); s1.flush(); } catch (system_error& e) { return 1; } } It does not make sense, still 10 syscalls: connect(6, {sa_family=AF_INET, sin_port=htons(23380), sin_addr=inet_addr("127.0.0.1")}, 16) = 0 ioctl(6, FIONBIO, [1]) = 0 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 sendmsg(6, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="123", iov_len=3}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, MSG_NOSIGNAL) = 3 Is there a stream in asio that could buffer the multiple and small pieces of data into one syscall? |

2 1

Difference in regex_replace replacement format handling between Boost.Regex and std::regex
by Josué Andrade Gomes 22 Apr '24

22 Apr '24

There is a difference in how the replacement format string is handled by regex_replace in Boost.Regex and std::regex. Consider the following example: #include <iostream>#include <regex>#include <boost/regex.hpp> int main() { std::string s{"a:b:c"}; std::string rx{":"}; std::string r{"\\$&"}; // Using std::regex std::string result_std = std::regex_replace(s, std::regex(rx), r); std::cout << "std::regex result: " << result_std << std::endl; // Outputs "a\:b\:c" // Using Boost.Regex std::string result_boost = boost::regex_replace(s, boost::regex(rx), r); std::cout << "Boost.Regex result: " << result_boost << std::endl; // Outputs "a$&b$&c" return 0; } std::regex result: a\:b\:c Boost.Regex result: a$&b$&c Affects Boost.Regex 1.84. I didn’t try other versions. Tested with GCC 13.2, clang 18.10 , cl 19.39.33523 and results are the same. Not tested with other versions. https://github.com/boostorg/regex/issues/210

1 0

Regarding a Vulnerability in Boost.Regex library
by kamallochan Jena 18 Apr '24

18 Apr '24

Hello everyone, Hope you all are doing well. There is a Vulnerability reported on Boost library as mentioned below. Any guidance or assistance or reply to this mail would be greatly appreciated. *Vulnerability ID:* BDSA-2018-2656 *Vulnerability Details:* Boost has a flaw in the function boost::re_detail_NUMBER::basic_regex_creator which can lead to a buffer over-read. An attacker can craft and send a malicious file which will trigger the buffer over-read, leading to a denial-of-service. Few query w.r.t boost::re_detail_NUMBER::basic_regex_creator() function: 1. Does Boost.Regex library or any Boost library internally use this function? 2. If the answer is yes, Which all libraries use this function? 3. Is this a known vulnerability and is it fixed in the latest Boost version? please provide some insights like (any change list or file name etc). Our project uses a boost library(which has file "boost/regex/v4/basic_regex_creator.hpp") and uses Boost.Regex library functions. *Should we be worried about this vulnerability (BDSA-2018-2656) affecting our code? * Thanks!

2 1

Any idea on CWE-704(BDSA-2018-1263) and CWE-126 (BDSA-2018-2656)
by kamallochan Jena 15 Apr '24

15 Apr '24

Dear all, Could someone assist me in determining if any version of Boost library is vulnerable to the following CWE? BDSA-2018-1263 CWE-704 and BDSA-2018-2656 CWE-126 Additionally, I would appreciate any details regarding these vulnerabilities, such as - the specific version of the Boost library where the vulnerability was identified - the name of the source code file, the exact line of code and function that causes the vulnerability - Whether the latest version of Boost includes a fix, and if so, which version of the library it was addressed in. Any guidance or assistance on this matter would be greatly appreciated. Thanks, Kjena

1 0

Re: [Boost-users] [beast] I can't write a hello world server
by Senthil Cheetancheri 10 Apr '24

10 Apr '24

(Trying to repost because the previous message was rejected due to size limits.) Hi Loup, The reason I'm taking the time to ask here is because I feel there is something fundamental, likely obvious to the experts, that I don't understand about how beast (and, I'm guessing, asio) works, and how I'm supposed to use it. It seems like you are quite comfortable with C++. That is good because it is a necessary background for this. Boost.Asio and .Beast are inherently advanced topics. The examples use quite advanced C++ knowledge. It could appear simple to experts who understand asio and C++, as well as to newcomers if they were lucky to get the right orientation when they began to learn C++. I had to unlearn a lot of 'C' and old C++ notions. Here are some resources that helped me reach the Aha! moment after a lot of struggles. They are all well worth the patient time you will need. (They are from my bookmarks and are a bit dated. You can easily get the corresponding latest versions.) 1. ASIO: https://www.boost.org/doc/libs/1_79_0/doc/html/boost_asio.html 2. Beast: Watch this video https://youtu.be/7FQwAjELMek at the bottom of the tutorials page https://www.boost.org/doc/libs/1_80_0/libs/beast/doc/html/beast/examples.ht…. This video was a turning point for me. 3. If you would like interactive help, join the #beast channel of the cpplang slack https://cppalliance.org/slack/. They are very kind and super helpful. When you get asio and beast to work well, they are beautiful and give you joy. HTH. Thanks, Senthil.

2 3

Boost.ASIO C++ 20 coroutine equivalent of PPL task_completion_event or JavaScript Promise.resolve?
by Willem Mitchell 09 Apr '24

09 Apr '24

I'm trying to write a simple ASIO send/receiver that uses message queueing. The goal is to have a number of virtual streams over a single TCP connection. This is pretty simple using callbacks, but I can't figure out the coroutines alternative. Here is my simplified sample code. Note that I'm using asio::experimental::promise the same way I would use std::promise which obviously doesn't work, but it illustrates what I'm trying to do. What is the simplest solution to my problem? #pragma once #include "asio.hpp" #include "asio/co_spawn.hpp" #include "asio/detached.hpp" #include "asio/experimental/co_composed.hpp" #include "asio/experimental/promise.hpp" #include "asio/use_awaitable.hpp" #include <coroutine> #include <cstdint> #include <map> #include <memory> #include <queue> struct Message { uint64_t id; uint64_t streamId; uint64_t priority; }; class NetworkConnection { public: NetworkConnection(asio::io_context &ioContext) : ioContext_(ioContext), sendTimer_(ioContext_), receiveTimer_(ioContext_){}; asio::awaitable<std::unique_ptr<Message>> receive(uint64_t streamId) { auto promise = std::make_shared< asio::experimental::promise<std::unique_ptr<Message>>>(); auto future = promise->get_future(); receives_[streamId] = promise; if (!receiving_) { receiving_ = true; co_spawn(ioContext_, startReceiving(), asio::detached); } co_return co_await future; } asio::awaitable<void> send(std::unique_ptr<Message> message) { auto promise = std::make_shared<asio::experimental::promise<void>>(); auto future = promise->get_future(); sends_[message->id] = promise; if (!sending_) { sending_ = true; co_spawn(ioContext_, startSending(), asio::detached); } co_await future; co_return; } private: asio::io_context &ioContext_; asio::steady_timer receiveTimer_; asio::steady_timer sendTimer_; std::map<uint64_t, std::shared_ptr< asio::experimental::promise<std::unique_ptr<Message>>>> receives_; std::map<uint64_t, std::shared_ptr<asio::experimental::promise<void>>> sends_; std::queue<std::unique_ptr<Message>> sendQueue_; bool receiving_ = false; bool sending_ = false; void completeSend(uint64_t messageId) { auto it = sends_.find(messageId); if (it != sends_.end()) { it->second->set_value(); // This resumes the send operation sends_.erase(it); // Clean up } } void completeReceive(std::unique_ptr<Message> message) { auto it = receives_.find(message->streamId); if (it != receives_.end()) { it->second->set_value( std::move(message)); // This resumes the send operation sends_.erase(it); // Clean up } } asio::awaitable<void> startReceiving() { while (!receives_.empty()) { // Simulate receiving a message sendTimer_.expires_after(std::chrono::seconds(1)); co_await sendTimer_.async_wait(asio::use_awaitable); auto message = std::make_unique<Message>(); message->id = 1; message->streamId = 1; message->priority = 1; completeReceive(std::move(message)); } receiving_ = false; co_return; } asio::awaitable<void> startSending() { while (!sends_.empty()) { sendTimer_.expires_after(std::chrono::seconds(1)); auto message = std::move(sendQueue_.front()); sendQueue_.pop(); co_await sendTimer_.async_wait(asio::use_awaitable); completeSend(message->id); } sending_ = false; co_return; } }; class Stream { public: Stream(std::shared_ptr<NetworkConnection> connection) : connection_(std::move(connection)) {} asio::awaitable<std::unique_ptr<Message>> receive() { co_return co_await connection_->receive(id_); } asio::awaitable<void> send(std::unique_ptr<Message> message) { message->streamId = id_; co_return co_await connection_->send(std::move(message)); } private: uint64_t id_; std::shared_ptr<NetworkConnection> connection_; };

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Re: [Boost-users] [beast] I can't write a hello world server
by Mohammad Nejati [ashtum] 08 Apr '24

08 Apr '24

> Then I wait almost 4 seconds for a successful compilation. `-O2` and `-Og -g` are worse at 6 seconds. You are right, Asio and Asio based libraries are usually heavily templated as they need to work with generic executors, buffers and stream types. There are new facilities in Asio for alleviating this issue like any_executor and any_completion_handler which you can utilize to implement async operations in a source file. > I figured I'd write a wrapper, that would confine boost/asio/beast includes to a single compilation unit. The API I'm aiming for looks like this I think you might just use `beast::http::request<string_body>` and `beast::http::response<string_body>` types, you don't need to include all header files, you can just include `boost/beast/http/message.hpp`. > And yet I can sense a potential problem right off the bat: in the `http_server()` function, we call `std::move(socket)`. This move seems to be mandatory here, because removing triggers a compilation error. My point is, it looks like upon incoming connection we move the socket out of its outer context, such that it is no longer bound to the IO context. Is this another error in the example? You don't need to pass a socket to acceptor, it has multiple overloads: https://www.boost.org/doc/libs/1_84_0/doc/html/boost_asio/reference/basic_s… One of them creates a socket and passes it to the completion token, so, you can use it like: acceptor.async_accept([](auto ec, auto socket){ // ... }); Regards, Mohammad On Thu, Apr 4, 2024 at 4:50 PM Loup VAILLANT via Boost-users <boost-users(a)lists.boost.org> wrote: > > Hello, > > So this is rather embarrassing. After working more than 2 days full time I can't even get the most basic code running. I've scoured the docs and tried to find some tutorial, no luck. My onboarding experience so far has been… less than perfect. > > The reason I'm taking the time to ask here is because I feel there is something fundamental, likely obvious to the experts, that I don't understand about how beast (and, I'm guessing, asio) works, and how I'm supposed to use it. Which is probably why seemingly innocuous changes to official example code are causing memory corruptions left and right. > > Let's start at the beginning. > > My first attempt with beast was getting this code to work: > https://www.boost.org/doc/libs/1_73_0/libs/beast/example/http/server/small/… > > Compiling it with `g++ -std=c++20`, gets me a compilation error, thankfully easily fixed. > Then I wait almost 4 seconds for a successful compilation. `-O2` and `-Og -g` are worse at 6 seconds. > > I know many developers would say a few seconds are no big deal (though wen we get to XKCD sword fights it kind of is), but my problem here is that I didn't want to wait every time I made a business logic change to my code. But since 95% of compilation time came from including a huge header-only library, I figured I'd write a wrapper, that would confine boost/asio/beast includes to a single compilation unit. The API I'm aiming for looks like this: > > struct Http_message { > std::unordered_map<std::string, std::string> headers; > std::string body; > }; > struct Http_request : public Http_message { > std::string method; > std::string target; > }; > struct Http_response : public Http_message { > int status; > }; > typedef std::function<Http_response(const Http_request &request)> response_cb; > void http_start(unsigned short port, response_cb on_respond); > > (Note 1: I want web sockets as well, but one problem at a time) > (Note 2: I tried wrapping around http::request and http::response more directly to avoid unnecessary copies, but I ran into lifetime issues.) > > To its credit, this small server example seemed to run well enough, and could serve as a starting point. Before I untangle the business code from the HTTP specific stuff though, I needed to simplify this example a bit. So *this* is my actual starting point: > > > #include <boost/beast/core.hpp> > #include <boost/beast/http.hpp> > > namespace beast = boost::beast; > namespace http = beast::http; > namespace net = boost::asio; > using tcp = boost::asio::ip::tcp; > > class http_connection : public std::enable_shared_from_this<http_connection> > { > public: > http_connection(tcp::socket socket) : socket_(std::move(socket)){} > > void start() > { > auto self = shared_from_this(); > http::async_read( > socket_, buffer_, request_, > [self](beast::error_code ec, std::size_t) { > if(!ec) { self->process_request(); } > }); > deadline_.async_wait( > [self](beast::error_code ec) { > if(!ec) { self->socket_.close(ec); } > }); > } > > private: > tcp::socket socket_; > beast::flat_buffer buffer_{8192}; > http::request <http::dynamic_body> request_; > http::response<http::dynamic_body> response_; > net::steady_timer deadline_ { > socket_.get_executor(), std::chrono::seconds(60) }; > > void process_request() { > response_.version(request_.version()); > response_.keep_alive(false); > response_.result(http::status::ok); > response_.set(http::field::server, "Beast"); > response_.set(http::field::content_type, "text/plain"); > beast::ostream(response_.body()) > << "Target = " << request_.target() << "\n" > << "Method = " << std::string(request_.method_string()) << "\n"; > response_.set(http::field::content_length, > std::to_string(response_.body().size())); > > auto self = shared_from_this(); > http::async_write( > socket_, response_, > [self](beast::error_code ec, std::size_t) { > self->socket_.shutdown(tcp::socket::shutdown_send, ec); > self->deadline_.cancel(); > }); > } > }; > > void http_server(tcp::acceptor& acceptor, tcp::socket& socket) > { > auto cb = [&](beast::error_code ec) { > if(!ec) {std::make_shared<http_connection>(std::move(socket))->start();} > http_server(acceptor, socket); > }; > acceptor.async_accept(socket, cb); > } > > int main(void) > { > auto const address = net::ip::make_address("0.0.0.0"); > unsigned short port = 8080; > net::io_context ioc {1}; > tcp::acceptor acceptor{ioc, {address, port}}; > tcp::socket socket {ioc}; > http_server(acceptor, socket); > ioc.run(); > return 0; > } > > > So far it works. It listens to port 8080, and a curl request or 3 to the server works as expected: > > > $ curl -XYOLO -v http://localhost:8080/foobar > * Trying 127.0.0.1:8080... > * Connected to localhost (127.0.0.1) port 8080 (#0) > > YOLO /foobar HTTP/1.1 > > Host: localhost:8080 > > User-Agent: curl/7.81.0 > > Accept: */* > > > * Mark bundle as not supporting multiuse > < HTTP/1.1 200 OK > < Connection: close > < Server: Beast > < Content-Type: text/plain > < Content-Length: 31 > < > Target = /foobar > Method = YOLO > * Closing connection 0 > > And yet I can sense a potential problem right off the bat: in the `http_server()` function, we call `std::move(socket)`. This move seems to be mandatory here, because removing triggers a compilation error. My point is, it looks like upon incoming connection we move the socket out of its outer context, such that it is no longer bound to the IO context. Is this another error in the example? > > Okay then, how about I pass the socket all the way by reference instead? Let the constructor get a `tcp::socket&`, store this in a `tcp::socket&` member variable, remove all the `std::move`. It compiles, it runs the first query, but at the second query my program just freezes. Or loops, I don't know. > > So that's the first thing. I am _really confused_ about how this socket is supposed to work. Why does it block when I remove the standard moves? Isn't it supposed to be the same socket bound to the same IO context all the way? And I don't think it falls out of scope before the program ends either, it lives on the stack of the `main()` function, and the `ioc.run()`we call at the end blocks until we're done with the async reads (which is, never). > > **Can someone explain to me what the hell is going on with this socket?** > > Right now though I can accept that some dark secret lies behind this `std::move()`, and leave it alone for now. > > Moving on, I'll just admit for the time being that something magical and forbidden lies between this mysterious `std::move()` and prudently leave it behind. Now it's working again, and I can move (no pun intended) to the next step: extracting the business logic to an external function. I start with a trivial extraction: > > void respond(http::response<http::dynamic_body> &response, > const http::request <http::dynamic_body> &request) > { > response.result(http::status::ok); > response.set(http::field::content_type, "text/plain"); > beast::ostream(response.body()) > << "Target = " << request.target() << "\n" > << "Method = " << std::string(request.method_string()) << "\n"; > } > > And modify `process_request()` accordingly: > > void process_request() { > response_.version(request_.version()); > response_.keep_alive(false); > response_.set(http::field::server, "Beast"); > respond(response_, request_); > response_.set(http::field::content_length, > std::to_string(response_.body().size())); > > auto self = shared_from_this(); > http::async_write( > socket_, response_, > [self](beast::error_code ec, std::size_t) { > self->socket_.shutdown(tcp::socket::shutdown_send, ec); > self->deadline_.cancel(); > }); > } > > That works, but this is not quite enough: my goal here is to isolate my user code from the overly long compilation times imposed by this huge boost::beast. Maybe I can include the request & response headers without pulling in the kitchen sink with it, but I don't quite trust it. So let's wrap the `http::response` in some class so I can keep my headers nice and small: > > > class http_response { > public: > http_response(http::response<http::dynamic_body> &response) > : response_(response) {} > > void set_status(int status) { > response_.result(status); > } > void set_header(const std::string &title, > const std::string &value) { > response_.set(title, value); > } > void set_body(const std::string &body) { > beast::ostream(response_.body()) << body; > } > > private: > http::response<http::dynamic_body> &response_; > }; > > > Nothing fancy. And with a forward declaration I should be able to avoid including the response in the header that defines that class. Now I need to modify my business code accordingly: > > > void respond(http_response &response, > const http::request<http::dynamic_body> &request) > { > response.set_status(200); > response.set_header("Content-Type", "text/plain"); > response.set_body( > "Target = " + std::string(request.target()) + "\n" + > "Method = " + std::string(request.method_string()) + "\n"); > } > > > Still not free from `http::request <http::dynamic_body>` yet, but one step at a time. And finally, I need to adjust `process_request()`: > > void process_request() { > response_.version(request_.version()); > response_.keep_alive(false); > response_.set(http::field::server, "Beast"); > http_response response(response_); > respond(response, request_); > response_.set(http::field::content_length, > std::to_string(response_.body().size())); > > auto self = shared_from_this(); > http::async_write( > socket_, response_, > [self](beast::error_code ec, std::size_t) { > self->socket_.shutdown(tcp::socket::shutdown_send, ec); > self->deadline_.cancel(); > }); > } > > > Huh, what do you know, this time around it worked. I no longer experience the lifetime issues I've once had. Okay, I guess I'll add the request wrapper, then: > > > class http_request { > public: > http_request(const http::request<http::dynamic_body> &request) > : request_(request) {} > > std::string target() const { return std::string(request_.target()); } > std::string method() const { return std::string(request_.method_string()); } > > private: > const http::request<http::dynamic_body> &request_; > }; > > void respond(http_response &response, const http_request &request) > { > response.set_status(200); > response.set_header("Content-Type", "text/plain"); > response.set_body( > "Target = " + request.target() + "\n" + > "Method = " + request.method() + "\n"); > } > > void process_request() { > response_.version(request_.version()); > response_.keep_alive(false); > response_.set(http::field::server, "Beast"); > http_response response(response_); > http_request request (request_); > respond(response, request); > response_.set(http::field::content_length, > std::to_string(response_.body().size())); > > auto self = shared_from_this(); > http::async_write( > socket_, response_, > [self](beast::error_code ec, std::size_t) { > self->socket_.shutdown(tcp::socket::shutdown_send, ec); > self->deadline_.cancel(); > }); > } > > > And it still works! Maybe it'll work out in the end? > Regardless, thanks for the rubber ducking I guess. > > My first question remains though: what the hell is going on with the socket? Why can't I just pass a reference along? Why do we even need a move constructor? Is there some special semantics, or `boost::asio` specific arcane, I should be privy to? > > Loup. > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > https://lists.boost.org/mailman/listinfo.cgi/boost-users

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[release] Boost 1.85.0 beta 1 is available
by Marshall Clow 14 Mar '24

14 Mar '24

Boost release 1.85.0 beta 1 is now available at: https://boostorg.jfrog.io/artifactory/main/beta/1.85.0.beta1/source/ The SHA256 checksums are: c13b76f420684a8d5b2eb0f297c281348ba0311d50354d952c5ce7c689e7879b boost_1_85_0_b1.zip e65d529023c7b08d0b92c53fff24ce9df9568cc0fe667c90caf8a9dbc5e63b0d boost_1_85_0_b1.7z 9c1ce4793342e8e57eb34c61f774a9dac0c6fc036084785e416613a18091bacc boost_1_85_0_b1.tar.gz cf7449faedeac9b76bade8ee59007cc4456a14de375dfcbd9e6e38aabe8a1334 boost_1_85_0_b1.tar.bz2 There was one problem reported during the beta release process; when you build the release using b2, it will emit a warning: [errno 2] failed to scan file '': No such file or directory This is harmless, and will be fixed for the final release. the release notes are available at: https://www.boost.org/users/history/version_1_85_0.html Please try the beta and report any problems you encounter. Thanks to everyone who contributed to the release. -- Boost Release Team

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Can SIMD in boost unordered be disabled without disabling SIMD for full compile.
by Ivan Matek 13 Mar '24

13 Mar '24

Hi, I have some small maps where I am pretty sure SIMD tricks that are amazing in general will just slow down the lookups since I never lookup items not in the map and map is so small that benefits of not looking up into the big array and trashing the cache are miniscule. I know I can force compiler to not support SIMD with march, but I want to keep the SIMD optimizaitons for rest of the code, including large boost unordered objects. If you do not believe me I can write a custom benchmark, from what I see all benchmarks in docs start at 1E+4. P.S. I know I can just use an array, but I am in that "size range" where iteration becomes slower than a hash map. regards, Ivan

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Re: [Boost-users] Hi all,
by Pavel Vazharov 06 Mar '24

06 Mar '24

Hi, The most obvious error that I see is that you use `std::vector<char> buffer_data(1024);`as local variables and then they are destroyed but you continue to keep references to them via the boost::asio::buffer. The latter will not keep the `std::vector`s alive. You need to keep the std::vector as a member variable and only when you call the asio functions use the `boost::asio::buffer` function. Like m_socketHandler->socket.async_read_some(boost::asio::buffer(m_buffer_data), ... Where the m_buffer_data is a member variable of type `std::vector<char>`. HTH, Pavel.

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Hi all,
by Maria Tirindelli 06 Mar '24

06 Mar '24

I am experiencing an issue with boost 1.74 on linux. I am trying to have a server that asynchronously reads data from a tcp socket, and then closes when the client disconnect. My code looks like: class SimpleTCPServerTest::SocketHandler { public: explicit SocketHandler(boost::asio::ip::tcp::socket inputSocket ) : socket(std::move(inputSocket)) { socket.set_option(boost::asio::socket_base::keep_alive(true)); } boost::asio::ip::tcp::socket socket; }; SimpleTCPServerTest::SimpleTCPServerTest(std::string address, int port) : m_address(std::move(address)), m_port(port), m_ioc(boost::asio::io_context(1)), m_acceptor(boost::asio::ip::tcp::acceptor(m_ioc)), readTimer(m_ioc){ std::vector<char> buffer_data(1024); this->m_buffer = boost::asio::buffer(buffer_data); } bool SimpleTCPServerTest::open() { //auto const address = boost::asio::ip::make_address(ip); boost::asio::ip::tcp::endpoint endpoint(boost::asio::ip::tcp::v4(), static_cast<unsigned short>(m_port)); boost::system::error_code ec; // Open the acceptor m_acceptor.open(endpoint.protocol(), ec); if (ec) { LOG_ERROR("SimpleTCPServerTest", "Failed to open acceptor: " << ec.message()); return false; } // Allow address reuse m_acceptor.set_option(boost::asio::socket_base::reuse_address(true), ec); if (ec) { LOG_ERROR("SimpleTCPServerTest", "Failed to set reuse option in acceptor: " << ec.message()); return false; } // Bind to the server address m_acceptor.bind(endpoint, ec); if (ec) { LOG_ERROR("SimpleTCPServerTest", "Failed to bind acceptor: " << ec.message()); return false; } // Start listening for connections m_acceptor.listen(boost::asio::socket_base::max_listen_connections, ec); if (ec) { LOG_ERROR("SimpleTCPServerTest", "acceptor failed to start listening: " << ec.message()); return false; } m_acceptor.async_accept(boost::asio::make_strand(m_ioc), [this](boost::system::error_code ec, boost::asio::ip::tcp::socket socket) { on_accept(ec, std::move(socket)); }); m_iocRunThread = boost::thread([this] { m_ioc.run(); LOG_INFO("Exiting run thread"); }); return true; } } void SimpleTCPServerTest::on_accept(boost::system::error_code ec, boost::asio::ip::tcp::socket socket) { LOG_INFO("Client is connected"); m_socketHandler = std::make_unique<SocketHandler>(std::move(socket)); read(); } void SimpleTCPServerTest::read() { LOG_INFO("SimpleTCPServerTest", "Waiting a new message"); readTimer.expires_from_now(boost::posix_time::milliseconds(50)); readTimer.async_wait([this](boost::system::error_code ec) { LOG_INFO("Timer expired"); if (ec != boost::asio::error::operation_aborted) return; LOG_INFO("Timer expired with error"); m_socketHandler->socket.cancel(); }); m_socketHandler->socket.async_read_some(m_buffer, [this](const boost::system::error_code error, // Result of operation. std::size_t bytes_transferred) { if (error) { LOG_INFO("Client disconnected: " << error.message()); signalReadyToStop.emitSignal(); // HERE IT CRASHES return; } std::string dataString(boost::asio::buffer_cast<const char*>(m_buffer), bytes_transferred); LOG_INFO("Data was received: Size: " << bytes_transferred << " " << dataString); // Reset the buffer std::vector<char> buffer_data(1024); this->m_buffer = boost::asio::buffer(buffer_data); this->read(); }); } SimpleTCPServerTest::~SimpleTCPServerTest() { LOG_INFO("Terminating"); readTimer.cancel(); m_acceptor.cancel(); m_socketHandler->socket.cancel(); m_ioc.stop(); m_iocRunThread.join(); } The client is a simple python client that sends a few messages before disconnecting. my main.cpp is like: std::atomic<bool> m_runFlag = true; SimpleTCPServerTest server; server.signalReadyToStop.connect([&m_runFlag](){ m_runFlag =false; }); server.open(); while(m_runFlag) { std::this_thread::sleep_for(std::chrono::milliseconds(1000)); } LOG_INFO("Exiting test"); } The problem is that the code always crashes when returning from the async_read (indicated with "HERE IT CRASHES COMMENT") with error SIGABRT tcache_thread_shutdown(): unaligned tcache chunk detected. Even if I remove the return statement there, I still have the crash when calling m_ioc.stop(). It seems the error occurs when exiting from the m_iocRunThread (the "Exiting run thread" log is executed) What am I doing wrong? Thanks everyone

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tommath.h and boost\multiprecision\tommath.hpp
by Helmut Zeisel 28 Feb '24

28 Feb '24

I tried to use boost muiltiprecision with Visual Studio 2022, 64 bit and got the following error message: boost\multiprecision\tommath.hpp(444,36): error C2664: 'mp_err mp_radix_size(const mp_int *,int,size_t *)': cannot convert argument 3 from 'int *' to 'size_t *' I used tommath.h from https://github.com/libtom/libtommath/blob/develop/tommath.h that has (line 583) mp_err mp_radix_size(const mp_int *a, int radix, size_t *size) MP_WUR; but boost\multiprecision\tommath.hpp, lineS 443/444 are int s; detail::check_tommath_result(mp_radix_size(const_cast< ::mp_int*>(&m_data), base, &s)); I compared with cygwin, there tommath.h is mp_err mp_radix_size(const mp_int *a, int radix, int *size) MP_WUR; So I am not sure: do I need some different tommath for Visual Studio 2022, 64 bit, or should boost\multiprecision\tommath.hpp be changed? Helmut

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boost::stacktrace::stacktrace AND addr2line
by Foelsche, Peter 19 Feb '24

19 Feb '24

Dear All, Thanks for outstanding quality of boost! I'm using the stacktrace object together with debug info and BOOST_STACKTRACE_USE_ADDR2LINE defined. Would it be possible to cache the output of addr2line assuming that during the lifetime of the calling process the queried executable or shared objects do not change? Thanks Peter

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[boost::interprocess] between Rosetta and native apps - please advice how to fix issue
by Frank G 08 Feb '24

08 Feb '24

We need named IPC between Rosetta and native apps. In boost this seems not compatible, for example with Native app and we are unable to find the "MAP_FNAME" in find_and_construct on the Rosetta process. Works fine when each process is on same arch. " typedef boost::interprocess::managed_shared_memory shared_mem;shared_mem* seg;seg = new shared_mem(boost::interprocess::open_or_create, SHARED_FILENAME, F_MAX_TOTALBUF_SIZE );Img = seg->find_or_construct<imgtype>(MAP_FNAME)(); " Root cause seems to be MemoryAlgorithm and alignment.This has alignment of 16 for Rosetta and 8 for native.The 8 byte shift seems to be the root cause and I can see this when viewing memory. Looking deeper over the last few days we can see this from the difference in frontend size (from MemoryAlgorithm): "boost::interprocess::open_or_create This creates different sized frontend (iset_index 8 or 16)for Native vs Rosetta. frontend is defined from: boost::interprocess::ipcdetail::basic_managed_memory_impl<char, boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family>, boost::interprocess::iset_index, 16> *const Then perform segment->find_or_construct<mtstruct>(MAP_FNAME)(); does not work across arch." Ideally we prefer not to write a bunch of complex custom allocators etc to get this to work with open_or_create and find_or_construct, and hoping there is some simplest solution. Questions: how can we workaround this? Can we force boost::interprocess::open_or_create to use same memory algo for both arch? Or force alignment to 16 for both arch?

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Fwd: Using ASIO to wait on a foreign socket being readable, with a timeout
by Dominique Devienne 19 Jan '24

19 Jan '24

Sorry, sent originally to the wrong list. And this is on Windows 10 too, BTW. Haven't tried Linux with that code yet. --DD ---------- Forwarded message --------- From: Dominique Devienne <ddevienne(a)gmail.com> Date: Thu, Jan 18, 2024 at 7:18 PM Subject: Using ASIO to wait on a foreign socket being readable, with a timeout To: <boost(a)lists.boost.org> Hi, I'm trying to use ASIO to wait until a socket is ready to read, or timeout. This is a blocking wait. But the socket is not "owned" by ASIO, but is from the libpq PostgreSQL connection. So ASIO should NOT consume any of the input on the socket, just notify me when that socket is "read-ready". I've cobbled together the following test code: ``` const int socket2 = PQsocket(conn2.handle()); BOOST_CHECK(socket2 > 0); int timr_err_code = 0; int sock_err_code = 0; bool timr_aborted = false; bool sock_aborted = false; std::string timr_err_msg; std::string sock_err_msg; bool timed_out = true; auto c1 = "C# 1"sv; conn2.listen(c1); conn1->notify(c1, "wake up!"sv); { boost::asio::io_context io_ctx; boost::asio::ip::tcp::socket io_sock(io_ctx); io_sock.assign(boost::asio::ip::tcp::v4(), socket2); boost::asio::steady_timer io_timer(io_ctx); io_timer.expires_from_now(std::chrono::milliseconds(100)); io_sock.async_wait( io_sock.wait_read, [&](const boost::system::error_code& errc) { if (errc) { sock_err_code = errc.value(); sock_err_msg = errc.message(); sock_aborted = (errc == boost::asio::error::operation_aborted); } timed_out = false; //io_timer.cancel(); io_ctx.stop(); } ); io_timer.async_wait( [&](const boost::system::error_code& errc) { if (errc) { timr_err_code = errc.value(); timr_err_msg = errc.message(); timr_aborted = (errc == boost::asio::error::operation_aborted); } io_sock.cancel(); io_ctx.stop(); } ); io_ctx.run(); // blocks until either async op above runs } // there's a notif to read, so io_sock.async_wait should have completed BOOST_CHECK_EQUAL(timr_err_code, 0); BOOST_CHECK_EQUAL(sock_err_code, 0); BOOST_CHECK_EQUAL(timr_err_msg, ""); BOOST_CHECK_EQUAL(sock_err_msg, ""); BOOST_CHECK_EQUAL(timr_aborted, false); BOOST_CHECK_EQUAL(sock_aborted, false); BOOST_CHECK_EQUAL(timed_out, false); auto notif = conn2.notification(); BOOST_REQUIRE(notif); BOOST_CHECK_EQUAL(notif.backend_pid(), pid1); BOOST_CHECK_EQUAL(notif.channel(), c1); BOOST_CHECK_EQUAL(notif.payload(), "wake up!"sv); ``` The io_sock.async_wait(io_sock.wait_read, ...) succeeds, the IO loop stops as expected, but when I try to PQconsumeInput() from the LIBPQ connection next (as shown in the code below) ``` Notification Connection::notification() { auto [lock, hndl] = ensure_handle(); if (1 != PQconsumeInput(hndl)) { throw std::runtime_error(error_msg()); // <<<<<< THROWS } PGnotify_uptr notif{ PQnotifies(hndl) }; return Notification(std::move(notif)); // may be null } ``` that calls fail with this error message: fatal error: in "NotificationTests/test_across_backends": class std::runtime_error: could not receive data from server: Socket operation on non-socket (0x00002736/10038) LIBPQ didn't like what ASIO somehow did on the socket descriptor. The LIBPQ doc says to select() the descriptor, but I thought ASIO would be cleaner, more C++, and perhaps more cross-platform. Can somehow help, telling me if I'm using ASIO incorrectly here? Thanks, --DD

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[Scope] Peer review conclusion
by Дмитрий Архипов 15 Jan '24

15 Jan '24

Dear Boost community, the formal review of Boost.Scope has taken place between 26th of November and 5th of December of the previous year. I have received 5 reviews in total, including 4 here on the mailing list and 1 on Reddit. Two of the reviews recommended unconditional, and 3 conditional acceptance. The reviews came from: - Klemens Morgenstern, - Janko Dedic, - Julien Blanc, - David Sankel, - /u/jonesmz on Reddit. Also, several people have given insightful comments but did not provide a review. I would like to thank all of the people who took their time to write reviews or participate in the discussions. Your effort was very important and valuable. The outcome of the review is that Boost.Scope is ACCEPTED with several minor CONDITIONS. 1. noexcept specification on destructors of scope guards should be properly documented. Andrey has already commented that the technical hurdle that prevented it was eliminated. 2. There should be a good motivating example for scope_success. There was a lot of comments regarding scope_success and its seeming uselessness. Without a good example I see the same pattern occurring with future users. 3. The examples should better describe what they are trying to achieve. Several comments about examples suggested incorrect changes, which signals that readers failed to understand them. After a lot of consideration I decided against requesting the author to remove unique_resource and related functionality from the library. While several reviewers wanted a more "concise" library, all noted that the component is useful. One last thing I wanted to point out is that all reviewers and most commenters were adamant that compatibility with the Technical Specification on which this library was initially based should not be a goal. In fact, Andrzej Krzemienski even noted that such compatibility has prevented him from adequately evaluating the library on its own merit. In my opinion this should be a sign to all of us that people prefer better APIs over standard APIs. I recommend Andrey to re-evaluate those parts of the library's APIs that he copied from the TS and potentially pick better names for member functions. Thanks to Andrey for submitting this library to Boost. And thanks again to the reviewers and everyone who provided feedback, who ultimately made this review possible.

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