- Boost-users - lists.boost.org

[iostreams] Seeking with using stream<file_descriptor>::seekp() failes
by Timothy Madden 27 Sep '10

27 Sep '10

Hello Why do I get 'debug assertion failed: initialized_' when I try to seek on a boost::filesystem::stream<file_descriptor> ? I also tried with my own class seekable_fd: public device<seekable> { protected file_descriptor file_d; //.... }; to be use the device is seekable, and I get the same assert. I have boost 1.44.0, VS 2008, Win7 Thank you, Timothy Madden

1 1

Could searching and indexing Boost docs might work better?
by Paul A. Bristow 27 Sep '10

27 Sep '10

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of Steven Watanabe > Sent: Thursday, September 16, 2010 3:47 AM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] selective enabling/disabling of > BOOST_AUTO_TEST_CASE > > AMDG > > Suresh Kumar wrote: > > I have several tests in my unit test file each of them uniquely named > > using the function BOOST_AUTO_TEST_CASE. I may not need to run all of > > them always and as of now what I do is to comment out the tests which > > I dont want to run. > > > > Instead of commenting out code, is there any other way I can > > selectively enable or disable tests if i have created tests with > > BOOST_AUTO_TEST_CASE. > > > > You can control which tests are run on the command line See > http://www.boost.org/libs/test/doc/html/utf/user-guide/runtime-config/run- > by-name.html Well thanks Steven - Now that's something I have wanted to know but didn't dare ask ;-) But I have now squandered a few minutes trying again to find this information using Google (putting myself in the shoes of the OP). A search for "Running specific test units selected by their name" didn't get me to this page (on the first page at least). Adding site::boost.org helped reduce clutter from other unit test systems. Even "Running specific test units selected by their name" site:boost.org (note quotes mean search for exact text) didn't get to the current (or nearly) releases by name, and I didn't spot this page quickly. Using boost.org and entering "Running specific test units selected by their name" into the search box also didn't produce the latest docs page above, only out of date stuff. Limiting search to www.boost.org didn't get 1.44 docs (only misleading ref to 1.38). This may be why there are so many questions from puzzled users on this list? Is there anything we can do to make Google work better for us? Paul --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow(a)hetp.u-net.com

7 11

[regex] Boost.Regex + ICU vs. standalone ICU
by AJG 27 Sep '10

27 Sep '10

Hi there, Is there a document out there describing any substantial differences (in particular, w.r.t. semantics and correctness) between using Boost.Regex with ICU support baked in as opposed to ICU's built-in RegexMatcher/RegexPattern classes? I do realize, for example, that the former's API has a 'modern C++' style, whereas the latter is modeled on Java's -- but these differences seem to be mostly cosmetic. Is there anything else I should be aware of before deciding to use one or the other -- performance, functionality, ease-of-use, etc.? Thanks! PS: It doesn't look like xpressive has Unicode support yet, which is why I'm not considering it, but I'd love to know if this impression is false or soon-to-be false.

2 5

How to get the temporary directory ?
by Timothy Madden 27 Sep '10

27 Sep '10

Hello The new boost::filesystem::unique_path in V3 filesystem is great, but is there any way to also get the temporary directory ? A function that would return ::GetTempPath() on Windows systems and something like /tmp or /var/tmp on POSIX systems ? Or is there some portable way to do this already ? Thank you, Timothy Madden

1 0

Bjam problem - again
by Paul A. Bristow 26 Sep '10

26 Sep '10

I've moved to a new machine, and I can run bjam jobs from trunk, but when I try to run sandbox jobs, I am baffled by this message. Unable to load Boost.Build: could not find build system. --------------------------------------------------------- I:\boost-sandbox\boost-build.jam attempted to load the build system by invoking 'boost-build ;' but we were unable to find "bootstrap.jam" in the specified directory Unhelpfully, it doesn't seem to reveal what the 'specified directory' actually is. The files were copied over from a working system, so I can't see what has changed. The jamfile(s) are unchanged. I've got the following environment variables set: I:\boost-sandbox>set boost boost_build_path=i:\boost_1_44_0\tools\build\v2 boost_patches=i:\boost-patches boost_root=i:\boost_1_44_0 boost_sandbox=i:\boost-sandbox boost_trunk=i:\boost-trunk I:\boost-sandbox>bjam --debug_configuration just produces this message. I:\boost-sandbox>bjam -d5 --debug_configuration > debug.log produces the attached log, and the trunk log for comparison. Help! Thanks Paul PS Boost build is undoubtedly clever, but, sadly, not nearly clever enough for the abuse of very many users, judging by the Google entries for the above error message :-( --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow(a)hetp.u-net.com

3 5

best tool in Boost for (massive) string replacement?
by alfC 26 Sep '10

26 Sep '10

With all the tools available in Boost and coming from a different backgroup is hard for me to choose what is the best tool in Boost to do a massive string replacement. The problem I have is the following, I have a map of replaced and replacing strings std::map<string,string> rep; rep["\\alpha"] = "a"; rep["\\beta"] = "b"; ... let's say about 100 of these. And I have an input/output file (few thousand lines) were I would like to do all this replacements. What is the best tool in boost to do this, Spirit, Regex, tokenizer, StringAlgorithm? My only approach so far is Regex and the implementation is very crude. I read the file line by line and do a loop over the replacement keys for each line. It is not even exploiting the fact that I have a map of replacements (compared to an array of replacements). It seems very slow. (Yes, it is like a 'sed' unix command replacement but with hundreds of replacement strings) Thank you, Alfredo

4 3

[Proto] How to access the grammar of an expression?
by Roland Bock 24 Sep '10

24 Sep '10

Hi, ist there a way to access the grammar that was used to construct an expression? I have defined a metafunction template<class Left, class Right> struct grammar_less: mpl::false_ {}; which has specialization for some grammar combinations. Now I want to define a function that can take two arguments so that child0.grammar < child1.grammar Any idea how to do that? My test-code is attached. Regards, Roland

6 10

[Filesystem] String corruption in path in V3 and Boost 1.44
by Will Watts 24 Sep '10

24 Sep '10

I have the following method: boost::filesystem::path Sfw::CFolders::GetModulePath() { char buffer[MAX_PATH+1]; chknzapi (GetModuleFileName (NULL, buffer, MAX_PATH)); return buffer; // Converted to fs::path object } Under Boost 1.43 this seemed to work fine. The char buffer is used to create a temporary path object, which is returned by value from the function. But when I upgraded to Boost 1.44, and recompiled with BOOST_FILESYSTEM_VERSION=3 and BOOST_FILESYSTEM_NO_DEPRECATED defined, I found that, although it still compiled, it no longer worked properly. Specifically, the contents of the path becomes corrupted to garbage. I got the impression that the path object returned, instead of containing a copy of the character string, retains a pointer to the original char buffer[] on the stack - which is naturally trampled on by subsequent activity. Changing the function to this: boost::filesystem::path Sfw::CFolders::GetModulePath() { char buffer[MAX_PATH+1]; chknzapi (GetModuleFileName (NULL, buffer, MAX_PATH)); return string(buffer); } seems to fix the problem. I admit I have not examined the code for the filesystem::path class - I am roundly intimidated by Boost code. Is my problem caused by a bug in the library introduced by 1.44, or am I just using the library incorrectly? Is my fixed version acceptable, or am I just 'lucky' that it seems to work? The environment is Visual C++ 10, targetting 32-bit. As well as the #defines listed above, I have also got BOOST_NO_RVALUE_REFERENCES defined, to address a compilation problem with another Boost library. Regards Will PS: Apologies if this is a dupe. I attempted to post this via an NNTP account, which I believed had the correct rights, but didn't seem to do the business. Applied Industrial Systems is a limited company registered in England. Registered number: 2552260. Registered office: 11 Riverview, The Embankment Business Park, Stockport, Cheshire SK4 3GN.

3 9

[bind] Doubt regarding the use of shared_ptr with boost.bind
by Shiou Ming Lee 24 Sep '10

24 Sep '10

Hi, I have a doubt on using bind library. I pass the output of Bind to Asio library, and at certain point of time another thread will ask Windows I/O service to execute the function append(): m_ioService.post(m_strand.wrap( boost::bind(&LogWriter::append, (*logWritersItr), _logMessage, _logLevelString) )); The second param of Bind, (*logWritersItr), is a shared_ptr of LogWriter's subclass. The signature of LogWriter::append() is as following: virtual void append(const std::string& _logMessage, const std::string& _logLevelString) = 0; Base on document at http://www.boost.org/doc/libs/1_44_0/libs/bind/bind.html, the way I use bind will duplicate a copy of that shared_ptr. Any idea when will the duplicated shared_ptr become invalid so that the reference count decreases by one? Thanks, Shiou Ming

3 5

Can I call async_write twice in a row?
by Germán Diago 23 Sep '10

23 Sep '10

Is this legal? I think I understood in the documentation that it isn't, but I'm not sure if it means this: void func() { async_write(....); async_write(...); } So, should I do this ALWAYS? void func() { async_write(..., another_func); } void another_func(const boost::system::error_code & ec, std::size_t bytes) { async_write(...); } Thanks in advance.

3 2