May 2024 - Boost - lists.preview.boost.org

test7
by Sam Darwin 30 May '24

30 May '24

test7

1 0

NVCC and Unit Test Framework.
by Allen Sanderson 29 May '24

29 May '24

Hello, I am trying to sort out an odd crash on exit while using NVCC (via Kokkos-CUDA) and the Boost Unit Test Framework. Here my are data points: Kokkos-CUDA with the Boost test tool infrastructure - Crash Kokkos-HIP with the Boost test tool infrastructure - works Kokkos-Serial with the Boost test tool infrastructure - works Pure CUDA with the Boost test tool infrastructure - works Serial with the Boost test tool infrastructure - works Kokkos-CUDA alone (e.g. normal application) - works For the first case I have three scenarios (only used to high the Kokkos usage - the code does not crash in Kokkos::initialize), two of which crash: if(true) Kokkos::initialize(argc,argv); crash in CUDA - SEGFAULTif(false) Kokkos::initialize(argc,argv); crash in elsewhere - Subprocess aborted#if 0 Kokkos::initialize() #endif No crash For the first scenario the call stack is the following: #0 0x00001555521b5d9a in ?? () from ./cuda/12.2.0/lib64/libcudart.so.12 #1 0x00001555521b8c14 in ?? () from ./cuda/12.2.0/lib64/libcudart.so.12 #2 0x000015555219d882 in ?? () from ./cuda/12.2.0/lib64/libcudart.so.12 #3 0x00001555521a072b in ?? () from ./cuda/12.2.0/lib64/libcudart.so.12 #4 0x000015554b3b5797 in __cxa_finalize () from /lib64/libc.so.6 #5 0x0000155551301a87 in __do_global_dtors_aux () from build_kokkos_cuda/library/Operators/libOperators-g.so.5.5.0 #6 0x00007fffffffad10 in ?? () #7 0x000015555532dcee in _dl_fini () at dl-fini.c:141 For second, the call stack is quite deep after the call to __cxa_finalize () otherwise the first four (4-7) are the same. At this point the only culprit I can perhaps point at is nvcc I know at that previous versions of Boost and nvcc did not get along. And such, wondering if the usage is a corner case because I know of another project that is successfully using all three Boost, Kokkos, and CUDA. I am using Boost 1.85, Kokkos 4.3, and CUDA 12.2. Any insight or thoughts ? Our unit test work with Kokkos-HIP so able to validate results. Allen Sanderson SCI Institute University of Utah

1 0

[release] Boost 1.85.0
by Marshall Clow 28 May '24

28 May '24

Release 1.85.0 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.Charconv: A high quality implementation of <charconv> in C++11, from Matt Borland. * Boost.Scope: A collection of scope guard utilities and a unique_resource wrapper, from Andrey Semashev. 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_1.85.0> You can also download directly from: <https://boostorg.jfrog.io/artifactory/main/release/1.85.0/> 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

6 25

[container] Draft development plan for Boost.Container
by Ion Gaztañaga 28 May '24

28 May '24

Hi to all, Boost.Container was accepted in 2011 when container classes were spun off from Boost.Interprocess to form a new library. At that time it offered new features like emulated move semantics for "classic" STL-like containers and some new classes like flat_map and stable_vector. During these years more containers/main features were added: - The scoped allocator Model was added in Boost 1.50 (2012) - static_vector was added in Boost 1.54 (2013) - small_vector was added in Boost 1.58 (2015) - Polymorphic Memory Resources were added in Boost 1.60 (2015) - devector was added in Boost 1.75 (2020) Lately I've been collecting some ideas about how to improve the library and keep it interesting/useful both for other Boost libraries and Boost users. I've somewhat formalized a bit some of those ideas and I'd like to share them here in order to obtain feedback from the developers. Here's the document: https://docs.google.com/document/d/1VdMTheFUczC946dP3VKPseOoUq3sVKjU73oMvK8… Note that this document does not outline a schedule for all those ideas, it's an initial description of possible developments that should be evaluated/prioritized, as developing a substantial subset of the proposals would be a huge task. Thanks in advance for your attention and comments. Best, Ion

8 23

Docs in release tarballs
by Ruben Perez 24 May '24

24 May '24

Hi all, For someone that hasn't been that long involved in Boost, it feels strange to distribute the documentation in the same release tarball as the code, specially considering the usual complains about "Boost size". I'm sure there are reasons behind it, and I'd like to learn about them. This is a candid question, out of being a newbie here. Thanks, Ruben

4 7

OSTIF Boost security audit report
by Andrey Semashev 24 May '24

24 May '24

Hi, Recently, a security audit of several Boost libraries has been conducted. The audited Boost version was 1.83.0. The report is now published here: https://ostif.org/boost-audit-complete/ https://ostif.org/wp-content/uploads/2024/05/OSTIF-Boost-Report-PT-v1.4.pdf In short, the following libraries were audited: - Boost.Beast (1 medium issue) - Boost.DLL (1 informational issue) - Boost.Date_Time - Boost.Filesystem - Boost.GIL - Boost.Graph (1 low and 1 informational issues) - Boost.JSON - Boost.Program_Options - Boost.Regex (3 low issues) - Boost.String_Algo - Boost.URL - Boost.UUID No critical or high severity issues were identified. Of the 7 identified issues, 4 are marked as closed, meaning the issues are fixed. The remaining 3 are open and listed in Boost.Beast (medium), Boost.DLL (informational) and Boost.Graph (informational). During audit, several fuzzing harnesses were developed and added to OSS-Fuzz: https://github.com/google/oss-fuzz/tree/master/projects/boost In the report, there were also a few general recommendations given to improve project security: - Monitor OSS-Fuzz Reports - Implement a Vulnerability Disclosure Process - Implement Supply-Chain Attack Countermeasures - Improve the Documentation with Security Mechanisms and Assumptions - Avoid the Abuse of Asserts Also, one general recommendation to Boost users: - Perform Strict Input Validation You can find more details in the report. I'd like to emphasize the "Implement Supply-Chain Attack Countermeasures" part, which basically comes down to signing git tags and release tarballs. I think, our release process is indeed not very reliable, let's say, which showed during the past few releases: - there was instance when different tarballs for the same RC were generated from different git revisions - git tags for the release were missing or pointing to a wrong git commit Also, release tarballs on GitHub don't have hashsums or signatures attached. https://github.com/boostorg/boost/issues/838 For tarballs on jfrog, thankfully, there are hashsums published in the release notes. Perhaps, we could also publish .sig files for all tarballs, and also publish the public key to verify the signature on the website. Also, under "Implement a Vulnerability Disclosure Process" it is suggested to use GitHub Security Advisories[1] as the mechanism for reporting security issues. I've never used this tool, but perhaps it is worth enabling for boostorg on GitHub. Emailing library maintainers privately might not be a very reliable mechanism for such reports, given that maintainers may become inactive. [1]: https://docs.github.com/en/code-security/security-advisories/working-with-r…

5 10

Boost/CMake
by Robert Ramey 23 May '24

23 May '24

Anyone have first hand experience building/testing a boost library/application with CMake? I've found the github project for boost/Cmake. Can anyone point me to more useful information? Robert Ramey

15 41

Two mqtt libraries
by Robert Ramey 22 May '24

22 May '24

I've been contacted by my friend and sometime collaborator Takatoshi Kondo regarding his submission of a boost library: https://github.com/redboltz/async_mqtt. It has received two endorsements. He has asked me to be review manager and I'm inclined to accept this request as he was very helpful to me during the refinement of the boost serialization library. There is also mqtt client library that is proposed to the Boost. https://github.com/mireo/async-mqtt5 It also has endorsements and a review manager. A cursory examination of the git hub pages suggest considerable overlap between the two submissions. In general, boost has discouraged the acceptance of multiple libraries with this much overlap - and for good reason. An accepted library often becomes the canonical implementation in large parts of the C++ world. Having two high quality libraries that do almost the same thing is not where we would like to be. I would like to propose that we review both libraries simultaneously in order to try to reach a consensus as to which, if either we want to accept. I know this is a difficult task, but I think it is important that we do this. It's going to be tough to reject a well written library because a better one has been accepted. But it would be worse to reject a well written library merely because another one was submitted first. Normally I don't participate as a review manager as I'm pretty bogged down in Boost stuff as it is. But I'm willing to make an exception in this case due to the importance of this case and my strong personal ties to Takatoshi. BTW - who is the review wizard these days? I presume that he will be the one making the decision about this. Robert Ramey

10 17

Re: [boost] modern logic classes
by g.peterhoff＠t-online.de 18 May '24

18 May '24

> At this point I'd like to know if it's possible to thread mathematically the N-bool problem and create a library for generic multidimensional bool that works with templates allowing to determine N at compile time. Because in the future we should have a 8-bool implementation, and so on... Theoretically, it would (probably) be possible to provide N-valued logics. But that is beyond my knowledge. bool3/bool4(Belnap) are still manageable. For N-valued logics N>4, mathematicians would have to be consulted (as I said: I am not one). If you are asking about such things, perhaps temporal logics could also be provided https://en.wikipedia.org/wiki/Temporal_logic. But that's where I completely drop out.

1 0

modern logic classes
by g.peterhoff＠t-online.de 18 May '24

18 May '24

Hello, I would like to provide modern logic classes, please see https://github.com/boostorg/logic/issues/30 What are your opinions/comments on this? thx Gero

8 15

2024 Q1 Transparency report
by Louis Tatta 16 May '24

16 May '24

Hello, Louis Tatta here, CEO of The C++ Alliance, Inc, a registered 501(c)(3) non-profit organization dedicated to the support of C++. This is our Q1 2024 transparency report regarding our charitable work for the Boost C++ Library Collection. First, some background on our operations. The C++ Alliance seeks out highly talented and experienced C++ experts and hires them, usually full-time, so they can focus completely on their open-source projects. Our Staff Engineers maintain existing Boost libraries, write new Boost libraries, and contribute to other Boost projects. We employ IT experts full-time to maintain and improve the infrastructure which supports Boost, including the legacy web server, the Drone continuous integration servers, the scripts used to deploy GitHub Actions for Boost repositories, and the scripts which publish the Boost release. In addition, we provide on-demand technical support services for Boost authors and maintainers who have infrastructure-related problems. The Boost Mailing List continues to be the premier place for high-quality discussion of the Boost libraries and tangential C++ Standards related topics. The C++ Alliance supports the use of the mailing lists going forward. We are upgrading it to the latest Mailman version and building an optional web-based front-end allowing interaction using only a browser. We continue to operate the Official C++ Language Slack Workspace ( https://cpp.al/slack) which hosts the most popular interactive discussions regarding the Boost libraries. The C++ Alliance sponsors a paid plan to provide full history, video and audio conferences, collaboration tools, and unlimited document storage for seventeen dedicated Boost library channels and one main Boost discussion channel. Our largest project for Q1 2024 is the continuation of work on the new Boost website. The new site is a C++ social media portal with rich support for user-generated content and a powerful back-end which has visibility into the contributions made on GitHub and the release process. This allows us to deliver an elevated user experience with the hopes of attracting fresh talent to Boost. Also, note that the graphics on the website are hand-drawn by our contract artist and reflect our level of commitment to ensure that Boost, to put it simply, looks good. In Q1 2024 there were a total of two Boost Formal Reviews. One of the reviewed libraries is authored by a C++ Alliance Staff Engineer. None of the reviews were managed by C++ Alliance team members. Out of a total of sixteen submitted reviews for the quarter, eight were from C++ Alliance team members. This quarter, we increased our efforts to build Boost’s social media presence. There were a total of six messages from the @Boost_Libraries X (formerly Twitter) account, all submitted by C++ Alliance team members. Three of them contained artwork from Bob Ostrom commissioned by us. Messages containing images get three times more engagement than text-only messages. We believe that the X platform has unique strategic value for informing newer generations about the Boost value proposition. A total of $406,000 was spent on Boost-related contributions, broken down thusly (and rounded to the nearest thousand): Staff Engineers Compensation $317,000 Website Software Development $64,000 Server Hosting $25,000 During Q1 2024 we employed a total of 12 individuals to contribute to Boost. Here is a high-level summary of accomplishments: Sam Darwin (Chief Technical Officer) * Boost website maintenance and administration * Boost per-pull-request documentation previews * Boost Release Process development, maintenance, and administration * Boost Mailman services maintenance and upgrade * Boost GitHub Actions self-hosted runner project development * Boost Drone service administration and maintenance * New Boost website deployment, administration, and development Dmitry Arkhipov (Staff Engineer) * Boost.JSON maintenance Alan de Freitas (Staff Engineer) https://cppalliance.org/alan/2024/05/07/AlanQ1Update.html * Boost.URL maintenance * Mr. Docs project management (https://mrdocs.com) * GitHub actions support scripts for Boost CI (https://alandefreitas.github.io/cpp-actions/cpp-actions/index.html) Christian Mazakas (Staff Engineer) * Boost.Unordered evolution project * Boost.Buffers development (new library) * Boost.Http.Proto, Boost.Http.Io development (new libraries) Krystian Stasiowski (Staff Engineer) * Boost.StaticString maintenance * Mr. Docs Lead engineer (https://mrdocs.com/) * Clang/LLVM contributions Peter Turcan (Senior Technical Writer) * Boost User Guide development (new documentation) * Boost Contributor Guide (new documentation) * Boost Formal Reviews (new documentation) Matt Borland (Staff Engineer) * Boost.Decimal (proposed library) * Multi (https://github.com/correaa/Boost-Multi) review manager * Boost.Math maintenance Ruben Perez * Boost.PFR integration and maintenance work * Boost.MySQL maintenance (new, accepted library) * Boost.Charconv * User Guide, Contributor Guide contribution (new documentation) Mohammad Nejati (Staff Engineer) * Boost.Http.Proto and Boost.Buffers (new libraries) * Boost-Gecko (full-text site search) * Boost.Beast maintenance Fernando Pelliccioni (Staff Engineer) * Mr. Docs development (https://mrdocs.com/) Spencer Strickland (Senior Web Developer) * New website front-end and scripting Joaquin M Lopez Munoz (Staff Engineer) * Boost.Unordered evolution project lead * Boost.Bimap * Boost promotion and new website

1 0

Decimal Floating Point Library Beta
by Matt Borland 16 May '24

16 May '24

Hello, For the past year Chris Kormanyos and I have been working on a new library to implement IEEE 754 decimal floating point types. We are pleased to announce the library is now in beta, and can be found at: https://github.com/cppalliance/decimal, and the documentation is at: https://cppalliance.org/decimal/decimal.html First, what are Decimal Floating Point Numbers? They are floating point numbers where the significand is stored in base-10 (decimal) instead of base-2 (binary). This means that numbers can be represented exactly avoiding cases such as the famous 0.1 + 0.2 != 0.3: https://0.30000000000000004.com. The library provides types decimal32, decimal64, and decimal128 as specified in IEEE 754 and STL-like functionality. The library is header-only, has no dependencies, and only requires C++14. It provides most of the STL functionality that you are familiar with such as <cmath>, <cstdlib>, <charconv>, etc. We are proceeding as a beta right now rather than pursuing complete boost review as we are missing STL features such as C++17 special math, and believe we can continue to increase performance. We do intend to go through the review process at a later time. Please give the library a go, and let us know how we can make it better. We look forward to any and all feedback. If you use the Cpplang slack channel I am active (from the Central European Time zone) on both #boost and #boost-decimal. On a personal note as of today I have also moved from being employed half-time to full-time with the C++ Alliance. This affords me a greater opportunity to develop and maintain new and existing Boost libraries. Matt Borland —- C++ Alliance Staff Engineer

8 15

Fwd: shared_mutex lock() issue
by Max 15 May '24

15 May '24

Hi, It looks like threads-devel is abandoned I posted here. I have tried boost::shared_mutex and found an issue. It looks like it doesn't work as expected. The problem is following code: void lock() { #if defined BOOST_THREAD_PROVIDES_INTERRUPTIONS boost::this_thread::disable_interruption do_not_disturb; #endif boost::unique_lock<boost::mutex> lk(state_change); state.exclusive_waiting_blocked=true; exclusive_cond.wait(lk, boost::bind(&state_data::can_lock, boost::ref(state))); state.exclusive=true; } On lines: state.exclusive_waiting_blocked=true; exclusive_cond.wait(lk, boost::bind(&state_data::can_lock, boost::ref(state))); Here the state is changed and new lock_shared() waits because can_lock_shared returns false in this case. It works as I think it should be. The when "old" readers unlocks mutex the last one unlock_shared() executes void unlock_shared() { ... if (state.no_shared()) { if (state.upgrade) { ... } else { state.exclusive_waiting_blocked=false; //lk.unlock(); } release_waiters(); } where resets state.exclusive_waiting_blocked value. Then notify 2 condition variables(in release_waiters): 1 for readers and 1 for writers. If the writer doesn't win this race and one of the waited readers will be the first one, the writer runs state_data::can_lock and it of course returns false. Then the writer goes to sleep again. But exclusive_waiting_blocked is still false. So in the high pressure of readers, this writer never gets a chance to get control in this case anymore until all readers are gone. This bug was introduced in 1.67 version, before the changes the code was: while (state.shared_count || state.exclusive) { state.exclusive_waiting_blocked=true; exclusive_cond.wait(lk); } but it not the same as (because exclusive_waiting_blocked reassigned): state.exclusive_waiting_blocked=true; exclusive_cond.wait(lk, boost::bind(&state_data::can_lock, boost::ref(state))) Best Regards, Maxim

1 0

Re: [boost] Problem with building 1.85.0
by Ted Lyngmo 15 May '24

15 May '24

Andrey Semashev wrote: > > If you're building Boost from git, you should run `./b2 headers` before building Boost. > > The output you posted is missing the actual compilation errors for these files. Check the earlier compiler messages for these files. Or run `./b2 -j8 --with-filesystem` to build specifically Boost.Filesystem and see the output. Ok, I added `./b2 headers` before `./b2 -j8 install` which didn't change anything that I could see. `./b2 -j8 --with-filesystem` then gave me this: ...patience... ...found 3209 targets... ...updating 46 targets... boost-install.generate-cmake-config- bin.v2/libs/headers/build/stage/boost_headers-config.cmake boost-install.generate-cmake-config- bin.v2/libs/filesystem/build/stage/boost_filesystem-config.cmake boost-install.generate-cmake-config-version- bin.v2/libs/headers/build/stage/boost_headers-config-version.cmake common.copy /home/ted/git/boost/stage/lib/libboost_atomic.so.1.85.0 ln-UNIX /home/ted/git/boost/stage/lib/libboost_atomic.so boost-install.generate-cmake-config- bin.v2/libs/atomic/build/stage/boost_atomic-config.cmake boost-install.generate-cmake-config-version- bin.v2/libs/atomic/build/stage/boost_atomic-config-version.cmake common.copy /home/ted/git/boost/stage/lib/libboost_atomic.a common.copy /home/ted/git/boost/stage/lib/cmake/BoostDetectToolset-1.85.0.cmake common.copy /home/ted/git/boost/stage/lib/cmake/boost_filesystem-1.85.0/boost_filesystem-config.cmake common.copy /home/ted/git/boost/stage/lib/cmake/Boost-1.85.0/BoostConfig.cmake common.copy /home/ted/git/boost/stage/lib/cmake/Boost-1.85.0/BoostConfigVersion.cmake common.copy /home/ted/git/boost/stage/lib/cmake/boost_headers-1.85.0/boost_headers-config.cmake common.copy /home/ted/git/boost/stage/lib/cmake/boost_headers-1.85.0/boost_headers-config-version.cmake common.copy /home/ted/git/boost/stage/lib/cmake/boost_atomic-1.85.0/boost_atomic-config-version.cmake common.copy /home/ted/git/boost/stage/lib/cmake/boost_atomic-1.85.0/libboost_atomic-variant-shared.cmake boost-install.generate-cmake-config-version- bin.v2/libs/filesystem/build/stage/boost_filesystem-config-version.cmake common.copy /home/ted/git/boost/stage/lib/cmake/boost_atomic-1.85.0/boost_atomic-config.cmake common.copy /home/ted/git/boost/stage/lib/cmake/boost_atomic-1.85.0/libboost_atomic-variant-static.cmake common.copy /home/ted/git/boost/stage/lib/cmake/boost_filesystem-1.85.0/boost_filesystem-config-version.cmake gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/unique_path.o libs/filesystem/src/unique_path.cpp:57:10: fatal error: boost/scope/unique_fd.hpp: No such file or directory 57 | #include <boost/scope/unique_fd.hpp> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ compilation terminated. "g++" -fvisibility-inlines-hidden -fPIC -m64 -pthread -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_DYN_LINK=1 -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_FILESYSTEM_HAS_DIRENT_D_TYPE -DBOOST_FILESYSTEM_HAS_FALLOCATE -DBOOST_FILESYSTEM_HAS_FDOPENDIR_NOFOLLOW -DBOOST_FILESYSTEM_HAS_INIT_PRIORITY -DBOOST_FILESYSTEM_HAS_POSIX_AT_APIS -DBOOST_FILESYSTEM_HAS_STATX -DBOOST_FILESYSTEM_HAS_STAT_ST_BLKSIZE -DBOOST_FILESYSTEM_HAS_STAT_ST_MTIM -DBOOST_FILESYSTEM_NO_CXX20_ATOMIC_REF -DBOOST_FILESYSTEM_SOURCE -DNDEBUG -I"." -I"libs/filesystem/src" -c -o "bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/unique_path.o" "libs/filesystem/src/unique_path.cpp" ...failed gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/unique_path.o... gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/unique_path.o libs/filesystem/src/unique_path.cpp:57:10: fatal error: boost/scope/unique_fd.hpp: No such file or directory 57 | #include <boost/scope/unique_fd.hpp> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ compilation terminated. "g++" -fvisibility-inlines-hidden -m64 -pthread -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_STATIC_LINK=1 -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_FILESYSTEM_HAS_DIRENT_D_TYPE -DBOOST_FILESYSTEM_HAS_FALLOCATE -DBOOST_FILESYSTEM_HAS_FDOPENDIR_NOFOLLOW -DBOOST_FILESYSTEM_HAS_INIT_PRIORITY -DBOOST_FILESYSTEM_HAS_POSIX_AT_APIS -DBOOST_FILESYSTEM_HAS_STATX -DBOOST_FILESYSTEM_HAS_STAT_ST_BLKSIZE -DBOOST_FILESYSTEM_HAS_STAT_ST_MTIM -DBOOST_FILESYSTEM_NO_CXX20_ATOMIC_REF -DBOOST_FILESYSTEM_SOURCE -DBOOST_FILESYSTEM_STATIC_LINK=1 -DNDEBUG -I"." -I"libs/filesystem/src" -c -o "bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/unique_path.o" "libs/filesystem/src/unique_path.cpp" ...failed gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/unique_path.o... gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/directory.o libs/filesystem/src/directory.cpp:42:10: fatal error: boost/scope/unique_fd.hpp: No such file or directory 42 | #include <boost/scope/unique_fd.hpp> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ compilation terminated. "g++" -fvisibility-inlines-hidden -fPIC -m64 -pthread -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_DYN_LINK=1 -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_FILESYSTEM_HAS_DIRENT_D_TYPE -DBOOST_FILESYSTEM_HAS_FALLOCATE -DBOOST_FILESYSTEM_HAS_FDOPENDIR_NOFOLLOW -DBOOST_FILESYSTEM_HAS_INIT_PRIORITY -DBOOST_FILESYSTEM_HAS_POSIX_AT_APIS -DBOOST_FILESYSTEM_HAS_STATX -DBOOST_FILESYSTEM_HAS_STAT_ST_BLKSIZE -DBOOST_FILESYSTEM_HAS_STAT_ST_MTIM -DBOOST_FILESYSTEM_NO_CXX20_ATOMIC_REF -DBOOST_FILESYSTEM_SOURCE -DNDEBUG -I"." -I"libs/filesystem/src" -c -o "bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/directory.o" "libs/filesystem/src/directory.cpp" ...failed gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/directory.o... gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/directory.o libs/filesystem/src/directory.cpp:42:10: fatal error: boost/scope/unique_fd.hpp: No such file or directory 42 | #include <boost/scope/unique_fd.hpp> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ compilation terminated. "g++" -fvisibility-inlines-hidden -m64 -pthread -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_STATIC_LINK=1 -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_FILESYSTEM_HAS_DIRENT_D_TYPE -DBOOST_FILESYSTEM_HAS_FALLOCATE -DBOOST_FILESYSTEM_HAS_FDOPENDIR_NOFOLLOW -DBOOST_FILESYSTEM_HAS_INIT_PRIORITY -DBOOST_FILESYSTEM_HAS_POSIX_AT_APIS -DBOOST_FILESYSTEM_HAS_STATX -DBOOST_FILESYSTEM_HAS_STAT_ST_BLKSIZE -DBOOST_FILESYSTEM_HAS_STAT_ST_MTIM -DBOOST_FILESYSTEM_NO_CXX20_ATOMIC_REF -DBOOST_FILESYSTEM_SOURCE -DBOOST_FILESYSTEM_STATIC_LINK=1 -DNDEBUG -I"." -I"libs/filesystem/src" -c -o "bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/directory.o" "libs/filesystem/src/directory.cpp" ...failed gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/directory.o... gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/operations.o libs/filesystem/src/operations.cpp:120:10: fatal error: boost/scope/unique_fd.hpp: No such file or directory 120 | #include <boost/scope/unique_fd.hpp> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ compilation terminated. "g++" -fvisibility-inlines-hidden -fPIC -m64 -pthread -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_DYN_LINK=1 -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_FILESYSTEM_HAS_DIRENT_D_TYPE -DBOOST_FILESYSTEM_HAS_FALLOCATE -DBOOST_FILESYSTEM_HAS_FDOPENDIR_NOFOLLOW -DBOOST_FILESYSTEM_HAS_INIT_PRIORITY -DBOOST_FILESYSTEM_HAS_POSIX_AT_APIS -DBOOST_FILESYSTEM_HAS_STATX -DBOOST_FILESYSTEM_HAS_STAT_ST_BLKSIZE -DBOOST_FILESYSTEM_HAS_STAT_ST_MTIM -DBOOST_FILESYSTEM_NO_CXX20_ATOMIC_REF -DBOOST_FILESYSTEM_SOURCE -DNDEBUG -I"." -I"libs/filesystem/src" -c -o "bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/operations.o" "libs/filesystem/src/operations.cpp" ...failed gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/operations.o... ...skipped <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem.so.1.85.0 for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>directory.o... ...skipped <p/home/ted/git/boost/stage/lib>libboost_filesystem.so.1.85.0 for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem.so.1.85.0... ...skipped <p/home/ted/git/boost/stage/lib>libboost_filesystem.so for lack of <p/home/ted/git/boost/stage/lib>libboost_filesystem.so.1.85.0... ...skipped <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem-variant-shared.cmake for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem.so.1.85.0... ...skipped <p/home/ted/git/boost/stage/lib/cmake/boost_filesystem-1.85.0>libboost_filesystem-variant-shared.cmake for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem-variant-shared.cmake... gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/operations.o libs/filesystem/src/operations.cpp:120:10: fatal error: boost/scope/unique_fd.hpp: No such file or directory 120 | #include <boost/scope/unique_fd.hpp> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ compilation terminated. "g++" -fvisibility-inlines-hidden -m64 -pthread -O3 -finline-functions -Wno-inline -Wall -fvisibility=hidden -DBOOST_ALL_NO_LIB=1 -DBOOST_ATOMIC_STATIC_LINK=1 -DBOOST_COBALT_USE_STD_PMR=1 -DBOOST_FILESYSTEM_HAS_DIRENT_D_TYPE -DBOOST_FILESYSTEM_HAS_FALLOCATE -DBOOST_FILESYSTEM_HAS_FDOPENDIR_NOFOLLOW -DBOOST_FILESYSTEM_HAS_INIT_PRIORITY -DBOOST_FILESYSTEM_HAS_POSIX_AT_APIS -DBOOST_FILESYSTEM_HAS_STATX -DBOOST_FILESYSTEM_HAS_STAT_ST_BLKSIZE -DBOOST_FILESYSTEM_HAS_STAT_ST_MTIM -DBOOST_FILESYSTEM_NO_CXX20_ATOMIC_REF -DBOOST_FILESYSTEM_SOURCE -DBOOST_FILESYSTEM_STATIC_LINK=1 -DNDEBUG -I"." -I"libs/filesystem/src" -c -o "bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/operations.o" "libs/filesystem/src/operations.cpp" ...failed gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/operations.o... ...skipped <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem.a(clean) for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>directory.o... ...skipped <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem.a for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>directory.o... ...skipped <p/home/ted/git/boost/stage/lib>libboost_filesystem.a for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem.a... ...skipped <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem-variant-static.cmake for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem.a... ...skipped <p/home/ted/git/boost/stage/lib/cmake/boost_filesystem-1.85.0>libboost_filesystem-variant-static.cmake for lack of <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem-variant-static.cmake... ...updated 30 targets... ...skipped 10 targets... <p/home/ted/git/boost/stage/lib/cmake/boost_filesystem-1.85.0>libboost_filesystem-variant-shared.cmake <p/home/ted/git/boost/stage/lib/cmake/boost_filesystem-1.85.0>libboost_filesystem-variant-static.cmake <p/home/ted/git/boost/stage/lib>libboost_filesystem.a <p/home/ted/git/boost/stage/lib>libboost_filesystem.so <p/home/ted/git/boost/stage/lib>libboost_filesystem.so.1.85.0 <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem-variant-static.cmake <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem.a <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem.a(clean) <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem-variant-shared.cmake <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem.so.1.85.0 ...failed updating 6 targets... gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/directory.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/operations.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/unique_path.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/directory.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/operations.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/unique_path.o

4 4

Problem with building 1.85.0
by Ted Lyngmo 13 May '24

13 May '24

Hi! First, I'm not sure if this is the right place for this. https://svn.boost.org/trac/boost seems to be down so I'm not sure where to turn. When I try building 1.85 on Fedora 40 with g++ (GCC) 14.1.1 20240507 (Red Hat 14.1.1-1) I run into a problem. I'm preparing the build like this: git co master && \ git pull -r && \ git co boost-1.85.0 && \ git submodule update --recursive && \ ./bootstrap.sh --with-libraries=all --with-icu \ -with-python-version=3.12.3 --prefix=/home/ted/local && \ echo 'using mpi ;' >> project-config.jam Then building like this: ./b2 -j8 install It however ends like this: ... ...updated 18621 targets... ...skipped 30 targets... <p/home/ted/local/lib/cmake/boost_fiber-1.85.0>libboost_fiber-variant-shared.cmake <p/home/ted/local/lib/cmake/boost_filesystem-1.85.0>libboost_filesystem-variant-shared.cmake <p/home/ted/local/lib/cmake/boost_filesystem-1.85.0>libboost_filesystem-variant-static.cmake <p/home/ted/local/lib/cmake/boost_log-1.85.0>libboost_log-variant-shared.cmake <p/home/ted/local/lib/cmake/boost_log_setup-1.85.0>libboost_log_setup-variant-shared.cmake <p/home/ted/local/lib/cmake/boost_wave-1.85.0>libboost_wave-variant-shared.cmake <p/home/ted/local/lib>libboost_fiber.so <p/home/ted/local/lib>libboost_fiber.so.1.85.0 <p/home/ted/local/lib>libboost_filesystem.a <p/home/ted/local/lib>libboost_filesystem.so <p/home/ted/local/lib>libboost_filesystem.so.1.85.0 <p/home/ted/local/lib>libboost_log.so <p/home/ted/local/lib>libboost_log.so.1.85.0 <p/home/ted/local/lib>libboost_log_setup.so <p/home/ted/local/lib>libboost_log_setup.so.1.85.0 <p/home/ted/local/lib>libboost_wave.so <p/home/ted/local/lib>libboost_wave.so.1.85.0 <pbin.v2/libs/fiber/build/gcc-14/release/threading-multi/visibility-hidden>libboost_fiber-variant-shared.cmake <pbin.v2/libs/fiber/build/gcc-14/release/threading-multi/visibility-hidden>libboost_fiber.so.1.85.0 <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem-variant-static.cmake <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem.a <pbin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden>libboost_filesystem.a(clean) <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem-variant-shared.cmake <pbin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden>libboost_filesystem.so.1.85.0 <pbin.v2/libs/log/build/gcc-14/release/threading-multi/visibility-hidden>libboost_log-variant-shared.cmake <pbin.v2/libs/log/build/gcc-14/release/threading-multi/visibility-hidden>libboost_log.so.1.85.0 <pbin.v2/libs/log/build/gcc-14/release/threading-multi/visibility-hidden>libboost_log_setup-variant-shared.cmake <pbin.v2/libs/log/build/gcc-14/release/threading-multi/visibility-hidden>libboost_log_setup.so.1.85.0 <pbin.v2/libs/wave/build/gcc-14/release/threading-multi/visibility-hidden>libboost_wave-variant-shared.cmake <pbin.v2/libs/wave/build/gcc-14/release/threading-multi/visibility-hidden>libboost_wave.so.1.85.0 ...failed updating 6 targets... gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/directory.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/operations.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/link-static/threading-multi/visibility-hidden/unique_path.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/directory.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/operations.o gcc.compile.c++ bin.v2/libs/filesystem/build/gcc-14/release/threading-multi/visibility-hidden/unique_path.o Building boost-1.84.0, or earlier, the same way doesn't show any signs of problems. Is my bootstrapping done in the wrong way? I've used the same way for a long time, but I might just have been lucky that it has worked :) Br, Ted

2 1

What is this "Beman Project Development"?
by René Ferdinand Rivera Morell 12 May '24

12 May '24

I got the email below from discourse.boost.org (I had subscribed long ago). So getting something was not unexpected. What I'm wondering about are this: Q: What is this new "Beman Project Development" thing about? A: It's something from C++Now initiated by The Boost Foundation (DBA) Q: Did they get permission from the Beman family to use Beman Dawes' name this way? A: ?? ---------- Forwarded message --------- From: Jeff Garland via Beman Project <notifications(a)boost.discoursemail.com> Date: Fri, May 3, 2024 at 10:19 AM Subject: [Beman Project] [Beman Project Development] Becoming a member of the beman-project github Jeff-Garland <https://discourse.boost.org/u/jeff-garland> May 3 Please send your github id to @Jeff-Garland <https://discourse.boost.org/u/jeff-garland> @dsankel <https://discourse.boost.org/u/dsankel> or @bretbrownjr <https://discourse.boost.org/u/bretbrownjr> via DM. ------------------------------ Visit Topic <https://discourse.boost.org/t/becoming-a-member-of-the-beman-project-github…> or reply to this email to respond. To unsubscribe from these emails, click here <https://discourse.boost.org/email/unsubscribe/63382355ff9c551129d38f2a59078…> . -- -- René Ferdinand Rivera Morell -- Don't Assume Anything -- No Supone Nada -- Robot Dreams - http://robot-dreams.net

13 43

[boost.QVM] can you explain quaternions in the docs?
by Andrzej Krzemienski 12 May '24

12 May '24

Hi Everyone, I landed on this library docs when trying to learn what quarterions are for. Although the library has a vast documentation it doesn't explain what quaternions are and why they are used. When I was taught algebra for the purpose of computer graphics, vectors and matrices were on the table, but no quaternions. The examples show that I need to create a quaternion only to turn it into a rotation matrix. I am pretty sure there has to be more to it. Could I request an introduction section in the docs that would explain what quaternions are and why one would want to use them? The corresponding GitHub issue: https://github.com/boostorg/qvm/issues/51 Regards, &rzej;

5 5

What is this "Beman Project Development" exactly
by Robert Ramey 10 May '24

10 May '24

I confess that I'm totally mystified by this. I've looked over the web page and it doesn't help me. Here is the "mission statement" from the Boost Foundation website: "The Boost Foundation’s broad C++ mission is: (a) development of high quality, expert reviewed, legally unencumbered, open-source libraries, (b) inspiring standard enhancements, and (c) advancing and disseminating software development best practices. It does this by fostering community engagement, nurturing leaders, providing necessary financial/legal support, and making directional decisions in the event of Boost community deadlock." "Equally important to our mission is the guidance provided by our shared values. These are transparency, inclusivity, consensus-building, federated authorship, and community-driven leadership." Here is the "mission statement" from the Beman Project: "The Beman Project’s mission is to support the efficient design and adoption of the highest quality C++ Standard libraries through implementation experience, user feedback, and technical expertise. Founded at C++Now in 2024 the project strives to aggregate libraries proposed for ISO standardization making a simple usage experience for the C++ Community to try out new libraries. For library authors we assist by helping to make best modern development practices easy. Including CI, coverage, and packaging." Seems to me that they are essentially the same with different wording (excluding the woke paragraph it the Boost Foundation version. A couple miscellaneous questions: a) Why is the Boost Foundation website not part of the Boost.org website? b) So what's the point of all this? Who has promoted/championed it? What is their motivation. Extremely odd to me. add your own questions here. Personally I'd like to see the following: a) consolidation of all this under one umbrella b) More transparency in selection of board of directors. More direct influence on the part of library creators and users. I don't have any idea how to achieve this without creating caos though. c) Distancing Boost from the C++ standard. Boosts original mission was accomplished when the standards committee incorporated a large part of boost directly into the standard. Since then boost's policy of working with the standard library is very confusing. Are we an alternative? or are trying to create new (better?) standard library components. Or are we trying to create canonical implementations of the standard library components? The standard committee is flailing around itself. Three way branch? executors? Does something as elaborate as ranges belong in a standard library? What about testing the standard library? How do we do this? or Not. Do I incorporate the standard library in my heart pacemaker app? Without being able to test any of it? Oh let's not forget "modules" I've been reading up on it and it seems at most a half-baked idea. So boost should only focus on the standard to the extent that it needs to in order to make it's own libraries work. Sorry, I'm just not understanding any of this. Robert Ramey

7 11

Boost Foundation annual meeting in Aspen
by David Sankel 07 May '24

07 May '24

Hi all! We held our annual Boost Foundation meeting at C++Now last week. At this annual meeting we elect officers for an annual term and directors for staggering two-year terms. Glen Fernandes and Peter Dimov had terms expiring this year and were re-elected for another two-year term. We additionally added Matthew Guidry, who has been regularly active in foundation work, to the director roster. Congrats Matthew! Class A (Terms Expiring 2025) - Bob Steagall [BS] - David Sankel [DS] - Michael Caisse [MJC] - Zach Laine [ZL] - Inbal Levi [IL] - Jeff Garland [JG] - Kristen Shaker [KS] Class B (Terms Expiring 2026) - Glen Fernandes [GF] - Peter Dimov [PD] - Matthew Guidry [MG] - (4 vacant slots) We additionally made officer selections. I will continue for another year as Executive Director, but have stepped down as Chair of the Board of Directors. Kristen Shaker has volunteered to take this on (congrats Kristen!). Zach Laine has agreed to take on the Safety and Inclusion Chair role in her place. Here is the list of officers: - Board of Directors, Chair: Kristen Shaker - Board of Directors, Vice Chair: Glen Fernandes - Conference Chair: Bob Steagall - Director of Summer of Code: Inbal Levi - Executive Director: David Sankel - Secretary: Michael Caisse - Treasurer: Zach Laine - Standardization Chair: Jeff Garland - Safety and Inclusion Chair: Zach Laine We also decided to take down discourse.boost.org due to a general lack of interest by those active in the Boost project. The instance will be utilized by the Beman project <https://www.bemanproject.org/>, an independent initiative focused on providing implementations of libraries proposed for the C++ standard. That's all for now! -- David

1 0

Looking for review manager for async_mqtt
by Takatoshi Kondo 06 May '24

06 May '24

Hi, I've proposed a MQTT communication library based on Boost.Asio. https://github.com/redboltz/async_mqtt Fortunately, I got two endorsements, so far. Thank you Klemens and JoaquÃn. https://lists.boost.org/Archives/boost/2024/04/256650.php https://lists.boost.org/Archives/boost/2024/04/index.php However, I couldn't find a review manager, so far. https://www.boost.org/development/submissions.html I think that I am at step4 and step5 in the Boost Library Submission Process. I'm looking for review managers for async_mqtt now. I think that Boost.Beast, Boost.MySQL, and Boost.Redis are developed on Boost.Asio. I referred to those libraries for async_mqtt development. async_mqtt is using Boost.Beast for WebSocket communication. If those libraries developers would be interested in review managers, I would appreciate it. Of course, any other people are welcome. Best Regards, Takatoshi Kondo

1 0

GSOC '24 at Boost
by David Bellot 05 May '24

05 May '24

Hi all, Another year, another GSOC's coming! As you all know now, Inbal is in charge of managing our GSOC program at Boost. Over the past years, I had the pleasure to work with many of you and we had the chance to have many great students and mentors. This year, however, it seems we don't have enough mentors yet. I know it's just the beginning of the year, but I would like to encourage you to join this program as a mentor, and help students to participate in Boost and become great C++ developers. It's a very rewarding journey I took myself years ago and you will learn so much, both on the technical and human side. If you want to become a mentor, just add your name to this shared spreadsheet: https://docs.google.com/spreadsheets/d/1_eUWRsXnhi_JwKZbHZsGQf3WNUESsAPE4lV… Cheers, David

4 3

Compression libraries such as zlib and zstd ought to be first class boost libraries
by Nigel Stewart 05 May '24

05 May '24

Hello all, I've been having a fairly hard time enabling zlib and zstd for boost 1.85.0 so we can make use of the compression support in iostreams module. We do have some specifics - static linking, non-standard file names and not system-installed. Windows and Linux. For various reasons it looks like we're going to copy certain files into our modules, rather than puzzle over making this work. It's not ideal, but workable. But along the way it's become clear that this functionality is not first-class boost citizen. Such as the broken links in the documentation, and various historical questions via google reporting similar issues. There are also other copies of zlib in the beast tree, because it's obviously needed for HTTP stuff too. zstd too? So I did think that I should at least mention that zlib, zstd, bzip2 and xv-utils all ought to be promoted to first-class boost libraries even though the majority of the maintenance is coming from upstream. They ought to be part of the "big tarball" and enabled and built by default regardless of what happens to be installed on the system. The cmake stuff ought to "just work" the way it does for other boost modules. I'm not quite volunteering myself, but it seems like a start to pose the question. The developer experience could be significantly improved for this particular corner of things. - Nigel Stewart

7 24

Proposal for yet another MQTT library for Boost
by Takatoshi Kondo 01 May '24

01 May '24

Dear Boost Developers, I'd like to propose a MQTT library to the Boost Libraries. Repository link: https://github.com/redboltz/async_mqtt Document link: https://redboltz.github.io/async_mqtt/doc/5.0.0/index.html Here is characteristics of async_mqtt: - C++17 or later is required. - async_mqtt supports Boost.Asio style completion tokens. - e.g. use_future, deferred, use_awaitable, callback functions, etc - Not only MQTT client but also MQTT server is supported. - User can use this library to develop MQTT broker. - Sample MQTT broker application is included. - Both MQTT v3.1.1 and v5.0 are supported. - In addition, undetermined protocol version is supported for server implementation. In this case, the protocol version is decided when you receive CONNECT packet. - Continuous packet sending - Users can send the next MQTT packets before the previous sending is not completed (completion handler is not invoked yet). - Auto acquiring/mapping topic alias is supported. - In addition, when resending a PUBLISH packet after reconnecting, the topic alias is removed and the original topic is restored. It is required by MQTT v5.0 spec. - Packet based send()/recv() APIs. - MQTT has various packets and some of their fields are optional. In order to keep simple APIs, async_mqtt uses packet based APIs. - See https://redboltz.github.io/async_mqtt/doc/5.0.0/tutorial/send_recv.html - Layered archtecture - async_mqtt can have predefined TCP, TLS, WS, WSS, and user defined underlying layer. Users can access the underlying layer using next_layer() member function of MQTT endpoint. So you can configure any layers by yourself. e.g. tcp_no_delay, set send/recv buffer size, etc - See https://redboltz.github.io/async_mqtt/doc/5.0.0/tutorial/create_endpoint.ht… - High performance - See https://redboltz.github.io/async_mqtt/doc/5.0.0/performance.html Background I have developed another mqtt library mqtt_cpp https://github.com/redboltz/mqtt_cpp since 2015. It is widely used but has some limitations. For example: - The functions are directly mapped to packets(publish, subscribe, etc), so optional features are not designed cleanly. - Due to set_publish_hander / on_publish style handler design, Completion Token cannot be supported. Based on this 9years experience, I designed the new MQTT library. This is async_mqtt. I would appreciate if you could endorse this library. Regards, Takatoshi Kondo

3 4