March 2011 - Boost - lists.preview.boost.org

[review scoreboards]
by Sid Sacek 23 Mar '11

23 Mar '11

When I go onto sports web sites, they contain scoreboards for active games. The boost reviews are a bit like those active games. When a review starts, there generally is a huge flurry of emails that hits the boost mailing list, and a lot of heated debates go on in these mails. I generally don't have time to read through hundreds and hundreds of mails to get to the actual reviews. What I would like instead is an active scoreboard. It would contain a single page for a particular review, the current count of yeas and nays, the people who actually contributed to the reviews, and links to their reviews. It would also contain a final status of the review, and any contingent actions needed for completion. I assume this does not yet exist, and if not, how difficult would it be to set up something like this? Or maybe I should ask whether anyone else would prefer something like this? -Sid Sacek

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[aligned storage] namespace conflict
by Tobias Germer 22 Mar '11

22 Mar '11

Hi all, while patching the interprocess library (see ticket #5230) we found a namespace conflict in aligned_storage.hpp. The source refers to the (local) namespace "detail::". In the context of interprocess, this could be resolved to "boost::detail" or "boost::interprocess::detail", causing an ambiguity. I suggest to use the absolute namespace in aligned_storage, i.e., every "detail::" is replaced with "::boost::detail::" (see below for the patch). Are there any arguments against this? If nobody protests, Ion would apply the patch. Regards, Tobias Suggested patch: Index: aligned_storage.hpp =================================================================== --- aligned_storage.hpp (revision 70385) +++ aligned_storage.hpp (working copy) @@ -50,7 +50,7 @@ typename mpl::eval_if_c< alignment_ == std::size_t(-1) - , mpl::identity<detail::max_align> + , mpl::identity<::boost::detail::max_align> , type_with_alignment<alignment_> >::type align_; } data_; @@ -76,12 +76,12 @@ #else public #endif - detail::aligned_storage::aligned_storage_imp<size_, alignment_> + ::boost::detail::aligned_storage::aligned_storage_imp<size_, alignment_> { public: // constants - typedef detail::aligned_storage::aligned_storage_imp<size_, alignment_> type; + typedef ::boost::detail::aligned_storage::aligned_storage_imp<size_, alignment_> type; BOOST_STATIC_CONSTANT( std::size_t -- Dr. Tobias Germer | tgermer(a)think-cell.com Software Engineer think-cell Software GmbH | Chausseestr. 8/E | 10115 Berlin | Germany http://www.think-cell.com | phone +49 30 666473-10 | US phone +1 800 891 8091 Amtsgericht Berlin-Charlottenburg, HRB 85229 | European Union VAT Id DE813474306 Directors: Dr. Markus Hannebauer, Dr. Arno Schoedl

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Re: [boost] Missing Documentation on Building and Installing Documentation.
by Stirling Westrup 22 Mar '11

22 Mar '11

On Mon, Mar 21, 2011 at 7:25 PM, Julian Gonggrijp <j.gonggrijp(a)gmail.com> wrote: > Stirling Westrup wrote: > >> Julian Gonggrijp wrote: >> > I think you should consider the Boost tree to be your installation of > Boost. The additional copies of the headers and the libraries are just > for convenience. If you throw away the Boost tree, you throw away your > Boost installation together with the documentation that starts at > $BOOST_ROOT/index.html. If I were to simply untar Boost into my include directory I would end up with documentation files in my include directory, where they don't belong, and where my system will not look for them, and were I to build the libraries, they would end up putting large amounts of extraneous files into the my include directory. So, I generally approve of the fact that bjam is capable of building the libraries and installing them and the headers into the canonical locations for my system. The only problem is that bjam does not know about the documentation. All I want is someone to tell it how to relocate the docs. If this breaks any documentation, then arguably this is just as much of a bug as having headers that break when relocated, and can be addressed on a case-by-case basis. > > Note that Boost is not only targeted at Linux users. Moreover, the > getting started guide is very clear about the structure of the Boost > tree, including the location of the documentation. It may be clear about the structure of the Boost tree, but the fact that Installation guide provides an installation method makes the structure of the Boost tree appear irrelevant to everyone except the developers of Boost. -- Stirling Westrup Programmer, Entrepreneur. https://www.linkedin.com/e/fpf/77228 http://www.linkedin.com/in/swestrup http://technaut.livejournal.com http://sourceforge.net/users/stirlingwestrup

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[context review] Several Questions
by Artyom 22 Mar '11

22 Mar '11

Hello, Before I start working with this library for review I need a clarification of several statements to understand actual usefulness of this library: > > A context switch between threads costs usually thousands of CPU > cycles on x86 compared to a user-level context switch with few > hundreds of cycles. > Performance ----------- One of the first things I did when read this statement and take a look on measurements is to write my own benchmark of context switch. I've run it on: - Intel i5 2.5GHz CPU 2 cores 4 threads. - Linux x86_64, Ubuntu 10.10 And compared context switch performance using sched_yeild and jump_to. I used default boost::context<> settings and default build (against Boost-1.46.0) and used dummy switch to measure actual operations beyond the switching There were two threads giving each one a time quanta and measured how much time context switch takes (of course included some warm up) sched_yeild - 377us Boost.Contex - 214us Dummy - 10us All tests done on a single CPU using taskset 0x1 ./test params So finally I can see that Boost.Context does not behave **much** better then OS context switch? I understand that I probably used by default ucontext but it is default and this is how it is going to be shipped by most distributions as it would probably be the safest. I need to see rationale, limitations and so on, in very explicit way. Usefulness of N:M model (or even 1:M model) ------------------------------------------- Long time ago OS developers used N:M threading model where several kernel threads were mapped to several user-space thread: - Solaris < 9 or 10 - Linux <= 2.4, - FreeBSD < 8 All these OSs today moved to 1:1 model as most efficient one, so I can't buy it that N:M or even 1:N model in this case would give performance advantage. As you know, even POSIX 2008 deprecated ucontext at all. So I would like to see some very good and based rationale with description of specific use cases and examples. I understand that it may be very useful paradigm but as long as I see most of implementations move away of N:M model... Why do you bring it back despite of huge drawbacks users space threads have: like interaction with blocking system calls, interaction with physical CPUs and so on? -------------------- Thanks, I'd like to see an answer on this topics before I continue. Artyom

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[Review] Type Traits Extension ending tomorrow
by Joel Falcou 22 Mar '11

22 Mar '11

Dear All, The fast track review of Frédéric Bron's extensions to the Type Traits Library is ending tomorrow. If you plan to submit a review, please do so as soon as possible. Thanks in advance to all participants of the review. =========== What is it? =========== This extension adds 37 new traits corresponding to the following 37 operators: - binary: ==, !=,<,<=,>,>=, , +, -, *, /, %, +=, -=, *=, /=, %=, , &&, ||, ,&, |, ^,<<,>>,&=, |=, ^=,<<=,>>= - prefix: ++, --, +, -, !, ~, * - postfix: ++, -- Each trait can detect if the operator can be used with particular types and if needed, if the return type is convertible to some type. =================== Getting the library =================== The latest version can be downloaded by different ways: - from the vault with unix line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the vault with dos line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the sandbox:http://svn.boost.org/svn/boost/sandbox/type_traits/ The entry point of the documentation is type_traits/libs/type_traits/doc/html/boost_typetraits/category/value_traits/operators.html The library has been tested with: - MSVC 8, 9, 10 on Windows, - g++ 4.4.5 on Linux, - intel 10.0 and 11.1 on Linux. To test the library, the simplest is to untar the headers in your boost include directory. For this, you can download the header part of the extension: - from the vault with unix line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t… - from the vault with dos line ending: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=type_t…

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unit test report output stream
by Emy 22 Mar '11

22 Mar '11

Hi ! I've seen here : http://www.boost.org/doc/libs/1_40_0/libs/test/doc/html/utf/user-guide/test… http://www.boost.org/doc/libs/1_40_0/libs/test/doc/html/utf/user-guide/test… that it is possible to choose output stream location for what is logged during unit tests (log_level). I would like to know if it is possible to do the same thing with report, i.e. choose a custom output stream (report_level) ? I found this link : http://www.boost.org/doc/libs/1_40_0/libs/test/doc/html/utf/user-guide/test… http://www.boost.org/doc/libs/1_40_0/libs/test/doc/html/utf/user-guide/test… but it's pretty empty ... Thank you ! Emilie -- View this message in context: http://boost.2283326.n4.nabble.com/unit-test-report-output-stream-tp3396609… Sent from the Boost - Dev mailing list archive at Nabble.com.

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[filesystem] path does not use global locale's codecvt facet - bug or feature
by Artyom 22 Mar '11

22 Mar '11

Hello, Boost.Filesystem v3 uses wide path under windows and can convert it from the narrow one using codecvt facet, so I would expect if the global locale is some locale that has special codecvt facet installed boost.filesystem should use it, i.e.: int main() { boost::locale::generator locale_generator; std::locale::global(locale_generator("en_US.UTF-8")); // Now default codecvt facet is UTF-8 one. boost::filesystem::path p("שלום.txt"); boost::filesystem::ofstream test(p); } However this does not work as expected! I had found that you need to imbue locale explicitly: boost::filesystem::path p; p.imbue(std::locale()); // global one p = "שלום.txt"; boost::filesystem::ofstream test(p); Now it works. Should I open a ticket for this or this is "planned" behavior?

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Enums: naming question?
by Vicente Botet 22 Mar '11

22 Mar '11

Hi, I'm developing a scoped enum library that use an emulation wrapping the native enum on a class to get scoped enumerators. I need some traits, to get the native type from the emulation, and the coping class from the native one. In addition there is an underlying type that is used to store the enumerators. Next follows the names I have use in the library: native_type::type underlying_type::type scoping_type::type In addition I have defined some functions that make the conversions from these types template native_type::type native_value(ScopedEnum e); template underlying_type::type underlying_value(ScopedEnum e); I have defined all these under the boost::enums namespace. Do you have a better proposal for these (meta-)functions? If you need more details you can take a look in the sandbow/enums directory http://svn.boost.org/svn/boost/sandbox/enums/libs/enums/doc/html/index.html Best, Vicente P.S. Note native-type and native_value are yet in the doc as enum_type and enum_value. The tutorial is really in a very draft state :( -- View this message in context: http://boost.2283326.n4.nabble.com/Enums-naming-question-tp3388473p3388473.… Sent from the Boost - Dev mailing list archive at Nabble.com.

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Re: [boost] [asio] timer cancelling
by Ralf Globisch 22 Mar '11

22 Mar '11

Robert, FYI, I think it might be better to post asio related queries to the dedicated asio mailing list: https://lists.sourceforge.net/lists/listinfo/asio-users Regards, Ralf >>> "Mr. Robert G Palmer Jr." 03/21/11 3:28 PM >>> boost 1.45.0 WinXP SP3 What is the difference between boost::deadline_timer.cancel() and the cancellation that happens due to boost::deadline_timer.expires_from_now()? I'm doing an async_read_some() inside of a wrapper function I have written (based on http://lists.boost.org/Archives/boost/2007/04/120339.php) I have a read handler and a timer handler (I want the bytes read value and could probably combine the two handlers into one with the appropriate modification to the bind call). The read handler works, and then I cancel the timer, but the NEXT TIME I call the wrapper function, the timer hander fires with a boost::asio::error::operation_aborted. The timer object is local to the wrapper function, but the io_service is not, it is passed in, so it seems the io_service is holding onto the timer completion handler AND the fact that it was cancelled. Is there a way to clean this out before exiting my wrapper function? Is the 'expires_from_now()' calling the timer handler or is it the first call to run_one()? Thanks, -- Robert G. Palmer, Jr. robert.palmer(a)ingenutec.com _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost -- This message is subject to the CSIR's copyright terms and conditions, e-mail legal notice, and implemented Open Document Format (ODF) standard. The full disclaimer details can be found at http://www.csir.co.za/disclaimer.html. This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. MailScanner thanks Transtec Computers for their support.

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Re: [boost] linking error with serialization
by Eun-Sung Kim 21 Mar '11

21 Mar '11

> Are you linking to the serialization library? The serialization library > isn't header-only. How can I link to the serialization library? Please, tell me about that. --Kim

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