July 2006 - Boost - lists.preview.boost.org

Re: [boost] [shmem] error while closing the segment
by Ion Gaztañaga 10 Jul '06

10 Jul '06

> yes, the destructor performs two destroy calls in front of the close > call (see below). But it should not give a damn about, destroyed is > destroyed. The call of close should only delete objects that still > exists. I've printed out the name of the named shared object which > triggers the error (it's "shmDefinition"). If I comment out the two > lines which destroy my named shared objects in the destructor, it works. > Hmm, I don't know why it not work when I destroy the objects by hand. > But definitely it should not be done twice. You are right. But this indicates that you somehow have tried to erase the same object (in this case ("shmDefinition")) twice (maybe another process?). It should assert when using a pointer (because otherwise that could corrupt all the segment) when deleting the object (a debug protection like when trying to "operator delete" the same ptr two times). However, when destroying by name, a bool is returned, saying if the object has been destroyed or not (well the only problem is to found the name in the name-object index). So it should return false in the second case, instead of asserting. The only problem is that both name and pointer delete operation uses the same code, and only one should assert. Thanks for finding this! Please, erase that assertion from your code. I will do the same in Sandbox-CVS, while I find some other solution. Regards, Ion

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Minor exception lib changes
by Emil Dotchevski 10 Jul '06

10 Jul '06

Hello, I am contemplating a few minor changes to the exception library and I wanted to get some input before I implement them. First, I think that the function template failed should be renamed. Somehow, boost::failed doesn't feel right. Since English is not native to me, I really need help with this one. Second, I'm thinking of renaming wrap_string/get_string. Those names did make sense in the implementation I've been using in my own code, because the whole thing was in namespace except. Clearly, boost::get_string doesn't suggest that it's part of the exception library. I'm thinking of renaming them both to exception_string. So, stuffing a string at the time of the throw would look like this: throw failed<foo>() << exception_string<tag>("value"); To extract the string from an exception_info object, you'd do this: exception_info & xi; if( std::string const * s = exception_string<tag>(xi) ) .... Similarly, it makes sense to rename both wrap_errno/get_errno to exception_errno. Thanks for everyone's input! --Emil

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boost.shmem bugs
by Dmitry Smirnov 10 Jul '06

10 Jul '06

1. If you hasn't semaphore support in your glibc libraries (in my case it was without TLS) "sem_open" function will return (sem_t*)0 instead of (sem_t*)-1 as it is described in my system header "semaphore.h". Plese correct file "shared_memory.hpp" for using SEM_FAILED macros. Defines in "semaphore.h": /* Value returned if `sem_open' failed. */ #define SEM_FAILED ((sem_t *) 0) /* Maximum value the semaphore can have. */ #define SEM_VALUE_MAX (2147483647) 2. Unclear sinuation. I wrote bugous example program where I write some data in shared_message_queue in infinity cycle without any timeout. If you stop program by Ctrl+C "boost_shmem_shm_global_mutex" stays in locked state so program will not work from second start. If you include some timeout in cycle then program will work properly. Thank you for good job! \o/ Best Regards, Dmitry Smirnov Saint-Petersburg, Russia Slackware 10.2 gcc-3.4.4 kernel 2.6.13 glibc-2.3.6

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[function] Conflict with Boost.TR1
by John Maddock 10 Jul '06

10 Jul '06

Unfortunately another TR1 problem, in boost/function/detail/prolog.hpp we currently have: # include <cassert> # include <algorithm> # include <functional> // unary_function, binary_function The inclusion of <functional> here causes a circular dependency between the TR1 version of <functional> and <boost/function.hpp> leading to a long list of compile errors: simply including <boost/function.hpp> on it's own is enough to trigger these when the TR1 headers are in the include path. The only (ugly) fix I can offer at present is to use <boost/config/no_tr1/functional.hpp> in place of <functional>. Better suggestions, or policies welcomed, this is starting to become a maintenance nightmare.... John.

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tr1/test_function_tricky trickier than needed
by Peter Dimov 10 Jul '06

10 Jul '06

The only reason for test_function_tricky.cpp to not compile with boost::function is the presence of the following two lines: BOOST_STATIC_ASSERT((::boost::is_base_and_derived<std::unary_function<int, long>, std::tr1::function<long (int)> >::value)); BOOST_STATIC_ASSERT((::boost::is_base_and_derived<std::binary_function<int, char, double>, std::tr1::function<double (int,char)> >::value)); that check for the (highly questionable and not particularly relevant) requrement that function<> should derive from unary_function or binary_function in some cases. I think that these two lines need to be moved to a separate test.

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[Boost-bugs] [ boost-Support Requests-1519824 ] regex - perl syntax affects what gets matched
by SourceForge.net 10 Jul '06

10 Jul '06

Support Requests item #1519824, was opened at 2006-07-10 01:48 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=207586&aid=1519824&group_… Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None Status: Open Resolution: None Priority: 5 Submitted By: Nobody/Anonymous (nobody) Assigned to: Nobody/Anonymous (nobody) Summary: regex - perl syntax affects what gets matched Initial Comment: Hi, I'm trying to move from 1.32 to 1.33 (I need unicode), and it seems that 'what gets matched' have changed: it no longer matches the left-most longest match, but the first BFS of the expression. Ok. It is documented. But how do I pass that? The only way I found around it is using regex::no_perl_ex, but: 1. The change of 'what gets matched' is not documented (or I didn't find it), and therefore I'm not sure it does what I think it does. 2. There is no 'lookahead' anymore, and I need it. Is there a way to tell a perl regex to match the left- most longest? or is there another workaround? Thanks, Moddy. moddyt(a)itemfield.com ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=207586&aid=1519824&group_… ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Boost-bugs mailing list Boost-bugs(a)lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/boost-bugs

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Re: [boost] Exception lib?
by Sohail Somani 09 Jul '06

09 Jul '06

> -----Original Message----- > From: boost-bounces(a)lists.boost.org > [mailto:boost-bounces@lists.boost.org] On Behalf Of Emil Dotchevski > > Not to mention that the client can and will do it wrong. > > I don't want to make a huge deal out of this because > ultimately I don't mind > hiding the dynamic_cast in a function get_exception_info. But > I am arguing > that this abstraction is not necessary because the only > implementation > possible is through a dynamic_cast (at least I can't think of another > possibility). Well for some people the only way to fix a const correctness related error is to remove the const. I can imagine people doing all sorts of (wrong)casts. IMHO, I think the api should constrain that freedom seeing as there *is* only one right way to do it! Sohail

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Interest in a clone_ptr class?
by Kevin Spinar 09 Jul '06

09 Jul '06

Is there interest in a clone_ptr class to supplement the current smart_ptr library? A clone_ptr is a smart pointer which performs a deep copy of the pointed-to object whenever the clone_ptr is copied. Also, the polymorphic type is maintained, eg: clone_ptr<Base> p(new Derived); clone_ptr<Base> p2; p2 = p; /* p and p2 now point to different Derived objects */ I am aware that there is a policy_ptr library being constructed which will probably provide the same functionality as this clone_ptr; however, when is this policy_ptr library scheduled to be completed? With cvs.sourceforge.netcurrently appearing to be down I've been unable to find accurate information on the status of this library, but with the complexity involved in creating such a versatile smart pointer, I imagine policy_ptr will still be under construction for some time; whereas a clone_ptr class could be written rather quickly, considering the simplicity of it and using the existing smart_ptr library as a guide. Kevin Spinar spinarkm [at] uwec [dot] edu

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Fwd: [Boost-users] [format][patch][1.33.1][SunPro11] missing static_cast from void* to char*
by Marc Mutz 09 Jul '06

09 Jul '06

Hi, This patch is not in 1.34-rc1. What's the preferred way to submit those things? Thanks, Marc -- Marc Mutz -- marc(a)klaralvdalens-datakonsult.se, mutz(a)kde.org Klarälvdalens Datakonsult AB, Platform-independent software solutions

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[variant/mpl] increase in BOOST_MPL_LIMIT_LIST_SIZE not affecting #types a variant can hold
by Marc Mutz 09 Jul '06

09 Jul '06

Hi, Test case and compiler output (gcc 4.0.x/Linux) attached. Would be nice if someone with karma could add this (or something similar) to the regression tests for variant. Thanks, Marc -- Marc Mutz -- marc(a)klaralvdalens-datakonsult.se, mutz(a)kde.org Klarälvdalens Datakonsult AB, Platform-independent software solutions

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