July 2010 - Boost - lists.preview.boost.org

[interprocess] Superfluous "volatile" in atomic_add_unless32
by Capehart, Nolan 29 Jul '10

29 Jul '10

In this: inline bool atomic_add_unless32(volatile boost::uint32_t *mem, boost::uint32_t value, volatile boost::uint32_t unless_this) I think "volatile" on the last argument has no purpose and probably reduces speed slightly. Will it not merely cause the compiler to fetch the formal argument from memory every time it's needed? And isn't that of no use since nothing is modifying the formal argument during the function execution? So: 1) Caller puts actual argument on stack. 2) Caller calls atomic_add_unless32. 3) atomic_add_unless32 treats stack variable as volatile, wasting time (not much) because variable isn't actually changing.

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[gsoc] boost.heap update
by Tim Blechmann 29 Jul '10

29 Jul '10

hi all, i've uploaded a new snapshot of boost.heap. it includes some of the proposed changes and i have also added a benchmark sections. during the final time for the gsoc, i'd like to get the library ready for a review ... therefore, i uploaded a new snapshot [1] and an updated documentation [2]. feedback welcome ... cheers, tim [1] http://tim.klingt.org/code/attachments/download/31/boost_heap_280710.tar.gz [2] http://tim.klingt.org/boost_heap -- tim(a)klingt.org http://tim.klingt.org Cheat your landlord if you can and must, but do not try to shortchange the Muse. It cannot be done. You can't fake quality any more than you can fake a good meal. William S. Burroughs

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Phoenix3 port to proto complete
by Thomas Heller 29 Jul '10

29 Jul '10

Ladies and Gentlemen, I proudly announce that the port of phoenix3 is completed! All testcases pass! (some with minor modifications) So, What is next? Here is my proposed schedule: - fix some minor issues - improve boost.bind compatibility: make all boost.bind testcases pass - implement all boost.lambda testcases and make them pass, as far as it is reasonable - add support for C++0x lambdas - make interoperability testcases for std::function, boost::function - adapt the documentation - clean up code (some parts are a little messy as of now) - improve compile time Did I miss something? This is a very tight schedule, I may not be able to finish all points during the GSoC period. Any help will be appreciated. Additionally a review of the current code is highly appreciated to point out some defects that might exist. The code can be checked out at: https://svn.boost.org/svn/boost/sandbox/SOC/2010/phoenix3 I will be happy to answer your questions! Additionally I would like to thank Joel de Guzman and Eric Niebler for their great assistance and initial designs! Best Regards, Thomas Heller

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review request for boost.context
by Oliver Kowalke 29 Jul '10

29 Jul '10

Hello John, hello Ronald, could you add boost.context to the review queue please. boost.context allows to switch between execution contexts. The state of the context which will be left is saved and maybe resumed later. It is a kind of POSIX ucontext (fallback on POSIX platforms for boost.context) but provides assembler for some platforms (faster and some platforms doesn't implement POSIX ucontext because it is deprecaded -> ARM). thanks an best regards, Oliver

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[Boost] [Thread] Query: Stack Size
by Alapkumar Sinha 29 Jul '10

29 Jul '10

Hi, How can I change the default stack size for each new thread being created? Secondly is there a mechanism to set the stack size while creation? I read somewhere that the default stack size is 8MB which is heavy for my application. Please suggest. Regards, Alap ________________________________ This Email may contain confidential or privileged information for the intended recipient (s) If you are not the intended recipient, please do not use or disseminate the information, notify the sender and delete it from your system. ______________________________________________________________________

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[Interprocess] Query on Message queue
by Alapkumar Sinha 29 Jul '10

29 Jul '10

Hi, I have a requirement to have message type based receiving functionality, like the one provided by linux ipc "ssize_t msgrcv(int msqid, struct msgbuf *msgp, size_t msgsz, long msgtyp, int msgflg); " But the messagequeue implementation in boost only allows to set a priority of the message and does not provide a mechanism to wait on a messagequeue based on message type. Can someone tell me if there is a way out to get the above functionalities through boost as well. Regards, Alap ________________________________ This Email may contain confidential or privileged information for the intended recipient (s) If you are not the intended recipient, please do not use or disseminate the information, notify the sender and delete it from your system. ______________________________________________________________________

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[serialization] Padding for base64 dataflow iterators ?
by Timothy Madden 29 Jul '10

29 Jul '10

Hello Could the documentation page for dataflow iterators in the serialization library please state that: 1. using base64 iterators will /not/ add the padding '=' characters in the encoded data, that are present in the canonical encoding in RFC4648 (The Base16, Base32, and Base64 Data Encodings) ? 2. binary string to be encoded should be null-terminated, or the iterators will not pad the input stream of bits with 0s to reach a multiple of 6 bits, but rather use whatever bits follow after the last encoded byte in memory ? Just so the user knows she either has to ensure padding, or otherwise she should not expect the result to exactly follow the RFC, and the result might not be suitable for data interchange between applications, etc ... Or maybe the examples could be changed to include padding, which would be even better ... :) Thank you, Timothy Madden

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[placeholders]
by Andrzej Krzemienski 29 Jul '10

29 Jul '10

Hi, I have a problem with Boost.Bind placeholders. Namely, once I include the <boost/bind.hpp> it automatically brings placeholders _1, _2, .. into scope and I cannot use placeholders from other libraries like Spirit.Qi any more. I.e. I can but I need to qualify them like qi::_1, qi::_2, which is annoying. I include <boost/bind.hpp> in a precompiled header, so I have no option of not including it. Boost.Bind could define them in namespace boost::bind_placeholders and we could control their visibility with namespace using directive. This is what Spirit does, and it is cute. I guess I would not be able to convince anyone that Bind should do the same. But would it be possible to define placeholders _1, _2, ... as something more generic in Boost, unrelated to any particular library? Then boost::bind, would treat it as its own placeholders, Spirit semantic actions would treat them as its own placeholders, but they would be exactly same placeholders. Regards, &rzej

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[interprocess] cmake files on trunk
by Eric Niebler 28 Jul '10

28 Jul '10

Looks like some CMake build files were inadvertently committed to boost trunk (changeset https://svn.boost.org/trac/boost/changeset/64331) I say "inadvertent" because there's no way these files can work in isolation, considering that all other CMake support has been removed from boost trunk. Ion, can you please remove these files? Thanks, -- Eric Niebler BoostPro Computing http://www.boostpro.com

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thread_safe_ptr class interest request
by Philippe Vaucher 28 Jul '10

28 Jul '10

Hello, I've made a thread_safe_ptr class available at http://codepad.org/PxDEGaFm The idea is to use it like so: std::string data = "Hello world;"; thread_safe_ptr<std::string> data_ptr(&data); void thread1() { data_ptr->resize(3); } void thread2() { *data_ptr = "yeah"; } boost::thread t1(&thread1); boost::thread t2(&thread1); t1.join(); t2.join(); Do you see an obvious show-stopper for me not to continue developping this class? What's still to be done is worry about ownership of objects, my idea is to eventually somewhat model it after boost::shared_ptr that way it's easier to pass those around. When I'll be satisfied with the result, my plan is to "boostify" it (namespaces, license etc) and maybe propose it for inclusion in the smart pointer library. What are your thoughts? Philippe

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