January 2011 - Boost-users - lists.preview.boost.org

property tree child order
by Gianni Ambrosio 28 Jan '11

28 Jan '11

Hi All, can anybody tell me please if the property tree structure keeps the same child order of the related xml file? Regards Gianni

2 2

[range] Zip range adaptor
by Nathan Crookston 28 Jan '11

28 Jan '11

All, I've been using the boost range library for a few months now, and it's simplified my life considerably. I occasionally want to use something akin to MPL's zip_view and unpack_args with my ranges. For example: <code> const std::vector<int> vec1 = list_of(1)(2)(3)(4)(5)(6); std::vector<int> vec2 = list_of(10)(20)(30)(40)(50)(60); std::vector<int> vec3 = list_of(100)(200)(300)(400)(500)(600); boost::for_each(zip(vec1, vec2, vec3) | strided(2), unpack( std::cout << px::val('(') << arg1 <<", "<< arg2 <<", "<< arg3 << ")\n")); boost::transform(vec1, boost::begin(zip(vec3, vec2)), px::construct<boost::tuple<int,int> >(arg1 + 1, arg1 + 2)); boost::for_each(zip(vec2, vec3), unpack(std::cout << px::val('(') << arg1 << ", " << arg2 << ")\n")); </code> I note that the new algorithms include a two-argument for_each, but it would be nice to have something more extensible. I may have missed it in the documentation or on the list, but I haven't found anything like that. Does anyone know of such an adaptor? Since it's the weekend, I actually implemented code which allows the previous snippet to compile -- if no such adaptor exists I'd be happy to make it available/submit it to boost assuming there's interest. Thanks, Nate

4 7

BGL Properties
by David Doria 27 Jan '11

27 Jan '11

I have two questions: 1) I am trying to iterate through the edges of a graph and output their edge weights. I am confused though. I know how to output the "edges", but they are actually just a (vertex, vertex) pair which defines the edge. So do I index *edgePair.first into the EdgeWeightMap to get the weight of the edge starting from vertex *edgePair.first? Or how else would I get the weight associated with a particular edge? Code snippet: http://stackoverflow.com/questions/4810589/output-bgl-edge-weights 2) I have created a struct, and used it as a template parameter to adjacency_list. However, when I try to add_edge(vertex1, vertex2, property, graph) , the compiler complains "no matching function call". Can anyone see where I've gone wrong? Code snippet: http://stackoverflow.com/questions/4810235/bgl-bundled-properties-add-edge-… Any suggestions on either of these? Thanks, David

3 5

Boost thread: class member problem
by Patricia Hazel Shaw [phs] 27 Jan '11

27 Jan '11

Dear List members, I am trying to make use of threads within a class, but seem to be having problems with the syntax and getting it to compile. The outline of my class related to this thread issue is as follows: class Board{ public: void pressButton(int button); void boxAction(int box); private: boost::thread_group threads; }; void Board::pressButton(int button){ if(button=1){ threads.create_thread(&boxAction,1); } else ... } I have tried various different syntax within the create_thread() but have not been able to figure out from the documentation, or reading through the history of this mailing list, how to correctly do this. Any help you could give me would be greatly appreciated. Patricia Shaw

2 2

[Review][GIL] Boost.GIL IO and Toolbox extensions have been ACCEPTED into Boost
by Mateusz Loskot 27 Jan '11

27 Jan '11

Dear All, The formal review of IO and Toolbox extensions for Boost.GIL [1] ended on December 17th, 2010 [2] The review subject was not a standalone library but a part of whole - an extension to existing Boost.GIL. The review result: ACCEPTED Number of received discussion and feedback posts is ~140. I consider most of them in-topic, significant and also insightful. Reviewers pointed issues already known from previous discussions on the mailing list as well as new topics regarding the design and implementation of the extensions. Also, issues related to the library itself (Boost.GIL) were addressed. Some of them could be considered ideas for future works and improvements. It is remarkable, most (if not all) of the discussions were focused on the IO extension. None of the submitted reviews include comments to the Toolbox extension. Formally, the review concluded with 1 NO and 7 YES votes. Some of the YES votes are considered as conditional and number of changes were requested by the reviewers. The following changes should be addressed before the extensions appear in the Boost mainstream: 1. Documentation is adequate, but requires clean-up and fixing of lots of typos. 2. Additional tests are added to exercise currently untested error cases that result in a longjmp should be added. They should pass on all platforms officially supported by Boost. 3. Make sure the test images are license-free. If the license status is unknown, change them to other license-free images. 4. The requirements for adding new file formats / backends to be made more explicit. This means defining concept for a file format reader/writer, etc. and adding new file formats would constitute providing models for these concepts. 5. Support for reading images whose file format is unknown at compile time. That involves the ability to register file formats / backends, associate them with given extensions and then call the appropriate reader based on the extension of the file name. 6. Support for different backends for the same image formats. It appears that this can be done simply the same way a file format can be extended, i.e. have "png_libpng" and "png_lodepng" tags. 7. Support for efficient reading/writing of parts of images that are too large to fit in memory. There are two ways to proceed: one is to have an input/output iterator that enforces sequential access, and another is to allow for user-driven access at the cost of sometimes severe performance. The reviewers also posted a few suggestions that could improve quality of the two extensions, 1. Name of functions like read_int8, read_int16, read_int32, write_int8 in Device models suggest they return and accept signed integers, but they return and accept unsigned integers. The naming could be improved.. 2. Do some profiling and performance optimization of the most common formats. Add some test cases to measure speed of common scenarios. 3. Make sure the test cases provide complete coverage. For example, set a breakpoint in every method, every switch statement and branch. Run your tests and remove any breakpoints that are encountered. Look at the breakpoints that were not hit and add tests for them. 4. It would be great if Christian and Domagoj could join their efforts to take the best of their libraries (IO extension implementations) to the IO extension included in Boost.GIL and collaborate for the advanced features discussed in reviews. I would like to thank Edd Dawson, Zach Laine, Domagoj Saric, Roland Bock, Lubomir Bourdev, Tom Brinkman, Phil Endecott, Kenny Riddile for reviews and others who participated in discussions. Thanks also go to Christian Henning for great work. I would like conclude recalling short comment Lubomir Bourdev included in his review. In my opinion, it is a good summary of the Boost.GIL IO and Toolbox review and generally all discussions on this subject: *** The problem with I/O is that you can never declare success. All we can hope for is push the boundary as much as we can, and leave the rest for the next update. *** [1] http://lists.boost.org/boost-announce/2010/11/0273.php [2] http://lists.boost.org/boost-announce/2010/12/0279.php Best regards, -- Mateusz Loskot, http://mateusz.loskot.net Charter Member of OSGeo, http://osgeo.org Member of ACCU, http://accu.org

1 0

[unittest] How to only ignore child terminate?
by Firouzeh Jalilian 26 Jan '11

26 Jan '11

I have a code that is run from the tests that I am running which does child.terminate(). That is considered a system error, therefore, I would have to set catch_system_errors="no" in order to ignore it. But the downside is I miss the rest of system errors I might be interested in. How can I only ignore child.terminate() while running unittests? Thanks in advance

3 2

Aggregate a boost::array, initialize with initializer list -- how?
by Dave Steffen 26 Jan '11

26 Jan '11

Hi Folks, I've got a question about supporting brace initialization syntax. double a[] { 1,2,3 }; ok, always has been. boost::array<int, 3> b {{ 1,2,3 }} Needs double braces because there's one member data to be initialized, and we want to initialize that with {1,2,3}. Fine. Some compilers let you drop one set of braces; GCC 4.4 does, but produces a warning. Now, I make a class: template<size_t N> Vector { public: ... boost::array<double, N> data; }; Vector<3> v {{{1,2,3}}} Still OK: again in principle, I need three sets of braces. However, I'd like my Vector::data member to be private, but as soon as I do that, Vector isn't a POD any more, and the brace initialization no longer works. (I'm not sure if this is in line with the standard, or is a GCC 4.4 limitation.) No problem, std::initializer_list to the rescue: template<size_t N> Vector { public: Vector(std::initializer_list<double> i) : data{i} {} ... private: boost::array<double, N> data; }; Alas, boost::array has no constructor that takes an initializer_list: error: no matching function for call to ‘boost::array<double, 3ul>::array(std::initializer_list<double>&)’ note: candidates are: boost::array<double, 3ul>::array(const boost::array<double, 3ul>&) /usr/local/Boost/1.44/boost/array.hpp:57:17: note: boost::array<double, 3ul>::array() scons: *** [fast/Test/testVector.o] Error 1 Having poked through the standard, I can't see any way to convince the compiler to turn an initializer_list back into the semantic equivalent of a brace initializer. Does anyone know how to do this? Does boost::array need a constructor that takes initializer_lists? Thanks! -- Dave Steffen, Ph.D. - Software Engineer Numerica Corporation <http://www.numerica.us> 4850 Hahns Peak Drive, Suite 200 Loveland, Colorado 80538 main (970) 461-2000 x 227 Email: dave.steffen(a)numerica.us fax (970) 461-2004

2 2

Simple serial port demonstration with boost asio asynchronous I/O
by Jeff Gray 26 Jan '11

26 Jan '11

A couple of weeks ago I posted a simple asynchronous demonstration of a telnet client using boost asio TCP network code. I have changed this code to turn it into a simple serial terminal application using the serial port support in the new version of boost asio. It required no changes at all the the read or write code. I just altered the initialization to use a serial port instead of a socket. Note that this is not intended to show how a fully functional application would work. There are plenty of areas that are not handled in this code. But it shows the idea and it's easy to build on this once you've got it working. Hope this helps someone else get started... Jeff

3 2

[intprocess] Incorrect alignment in managed memory named allocations
by Kevin J. Arunski 26 Jan '11

26 Jan '11

It appears that the named allocation functions for the managed memory classes do not place constructed objects at the appropriate alignment for the requested type in all situations. Here is a simple example to illustrate the issue. #include <iostream> #include <boost/interprocess/managed_mapped_file.hpp> // alignment of 16 on i386 and x86_64 struct vector_of_double { long double x; long double y; long double z; }; int main() { namespace bip = boost::interprocess; { std::cout << "Alignment of vector_of_double is " << __alignof__(vector_of_double) << std::endl; bip::managed_mapped_file simple_file_mapping(bip::create_only, "simple_mapping", 65536); vector_of_double * test_vec = simple_file_mapping.construct<vector_of_double>("a named vector allocation")(); std::cout << "Resulting allocation is at address: " << test_vec << std::endl; } bip::remove_file_on_destroy("simple_mapping"); return 0; } On gcc targeting i386, this code prints: Alignment of vector_of_double is 16 Resulting allocation is at address 0x???????c Similar results on x86_64. It appears the resulting address is only aligned on a 4 byte boundary on 32 bit targets and 8 byte on 64 bit targets. Are there workarounds? I have tried explicitly setting the alignment parameter in the mapped region's index parameter to 16, but it did not change the result. I have tested the problem with anonymous allocations, and those do appear to be appropriately aligned. Only named allocations have the issue.

1 0

Merging Boostbook XML Files
by Faruk Kuşcan 25 Jan '11

25 Jan '11

Hello, I'm trying to merge two boostbook xml files into one. http://gcc.gnu.org/ml/libstdc++/2007-11/msg00029.html I had done everything in this link but could not merge boostbook xml files. Isn't there any xslt file called merge or something else which does this. If you know the way, how some boostbook xml files are merged togeter, I'll be very appreciated. Thanks fro your help. Faruk

2 2

template type asserting
by Kraus Philipp 25 Jan '11

25 Jan '11

Hello, I have written a template class and I would like tot "assert the type". My class should only use floating point types like double or float. Can I do this check with BOOST_STATIC_ASSERT or anything else? The class need not to use a "countable type" (math: in N). Thanks Phil

5 5

update on boost logger
by Jeff Graham 25 Jan '11

25 Jan '11

Hello everyone, Where can I find the logger that has been accepted into boost? I think it is here: http://boost-log.sourceforge.net/libs/log/doc/html/index.html ? According to this message it was accepted into boost on March 24, 2010, but subject to some critical fixes: http://lists.boost.org/boost-announce/2010/03/0256.php However, the changelog at the above sourceforge site was last updated in May 2010, and the ToDo/wish list seems lengthy. There seems no easy way to track the progress on the critical fixes, some which are performance related and are of concern to my projects. Any status on the fixes, informal review on the fixes, and if all will be done for 1.46? Thanks

2 2

Re: [Boost-users] [Preprocessor] Relative Addresses in BOOST_PP_FILENAME_1
by Hossein Haeri 25 Jan '11

25 Jan '11

Dear TONGARI, > Just make sure "Lib" is in the include path, then everything works fine > for me. So, here is a very strange observation I got after trying to strictly follow the above recommendation of yours: I added my current working directory to the include path and it worked! I always thought that that is already in ones include path (by default). My compilers have always found such files. It even happens that my other files (in the same directory) used to find Header.hpp even despite that strange error I used to get! :O > It would be fine in the Remarks section to add words like:"quoted > filename may not work with some compilers here, such as gcc..." Agree. Thanks a lot, --Hossein

2 1

Re: [Boost-users] [Preprocessor] Relative Addresses in BOOST_PP_FILENAME_1
by Hossein Haeri 25 Jan '11

25 Jan '11

Dear TONGARI, > Where I said <> I meant <something in compiler's include path>, that > works fine, just as Edward and Steven said. Well, my working directory is already in my compiler's include path. And, inside Header.hpp, the following line #define BOOST_PP_FILENAME1 <Header.hpp> fails to compiler in GCC 4.5.1 because GCC says it can't find Header.hpp. And, I am missing anything here? Maybe it's better that you tell me what you'd be writing instead of the line above if it would have been you... > If this is not a bug with a specific compiler, I hope at least it should > be noted in Boost.PP's doc. It's not. Both quote and angle brackets are mentioned to work in the specs: http://www.boost.org/doc/libs/1_45_0/libs/preprocessor/doc/ref/filename_x.h… TIA, --Hossein

3 3

Re: [Boost-users] Boost-users Digest, Vol 2613, Issue 3
by Loek Cleophas 25 Jan '11

25 Jan '11

On Mon, Jan 24, 2011 at 18:00, <boost-users-request(a)lists.boost.org> wrote: > Date: Mon, 24 Jan 2011 17:48:14 +0200 > From: Igor R <boost.lists(a)gmail.com> > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] [statechart] (custom) state queries for > asynchronous state machine > Message-ID: > <AANLkTim_eYbue02=dOA=0ouAi7wWDTaV9KWW0TXZ+Aum(a)mail.gmail.com<0ouAi7wWDTaV9KWW0TXZ%2BAum(a)mail.gmail.com> > > > Content-Type: text/plain; charset=UTF-8 > > > However, for the asynchronous case, access to the state machine is via a > > scheduler only - and I don't see how to get the information from there > nor > > is there any documentation on that in the tutorial. Any hints on how to > do > > this? > > With async. state machine such a direct access wouldn't be thread > safe. So the only way you can retrieve its state is by means of > events. I.e. you can enqueue an event, which contains some facility > for the response - like a ptr to a message queue or a slot for > boost.signals2 and so on. When processing this event, the machine > performs the query you want and returns you the answer through the > facility you provided. > Hi Igor, of course, that makes sense. I don't know why I didn't think of using a callback - but will try that now. Thanks for your prompt response, it's much appreciated! Loek

1 0

Iostreams code_converter peculiarities
by Eddie Carle 25 Jan '11

25 Jan '11

I've been working on converting a the fastcgi++ library over to using boost::iostreams from std::iostreams and I've noticed some peculiarities that I can't seem to work passed. For one, how do you change the buffer size of the code_converter adaptor? The built in facilities don't seem to actually do anything. I am adding to a filtering_stream and have noticed that for the following statements... stream.push(code_converter<MyDevice>(myDevice), 8192); stream.push(code_converter<MyDevice>(myDevice, 8192)); stream.push(code_converter<MyDevice>(myDevice, 8192), 8192); All result in a buffer of 128 bytes. I can't figure out a way to actually change it. I've been monitoring what is going in the myDevice and it is always 128 byte chunks (or less). If I remove the code_converter from the stream and go directly in myDevice as per stream.push(myDevice, 8192); the buffer is sized as I want it to be and myDevice receives chunks of data maxing at 8192 bytes. Secondly, when using the statement stream.push(code_converter<MyDevice>(myDevice, 8192)); code_converter calls not MyDevice(const MyDevice&) for copying constructing the object but for some reason MyDevice(const MyDevice&, const long int&). What is that? Why is code_converter looking for such a constructor when I specify a buffer size for the code converter? Thirdly, I can not for the life of me make the code converter flush it's data. If I call a stream.strict_sync() should the code_converter not get flushed as well? It doesn't. Everything else in the chain does but the code_converter won't fully flush until destruction. Thanks. -- Eddie Carle

1 0

Re: [Boost-users] reference access with boost::make_transform_iterator
by Patrick Sauer 25 Jan '11

25 Jan '11

Hi, I'm trying to use boost::make_transform_iterator to create an iterator for a custom class whose data is held in a map and where the iterator uses the vector of keys to access the values. In my problem, the values of the map are containers which hold large data. Since I can't afford to copy the data, I would like to access the data by reference via the iterator. However, when doing this, the data is corrupted, as is exemplified by the output of the simple example I have attached. As far as I can tell the problem lies in the use of the from_key functor, which is initialised using a reference to the map and is corrupted when passed through make_transform_iterator. Any ideas how I could do this properly using boost? Thanks, Patrick #include <iostream> #include <string> #include <vector> #include <boost/unordered_map.hpp> #include <boost/iterator/transform_ iterator.hpp> #include <boost/assign.hpp> #include <boost/assign/std/vector.hpp> #include <boost/lambda/lambda.hpp> #include <boost/lambda/bind.hpp> #include <boost/ref.hpp> using namespace boost::assign; namespace bl = boost::lambda; class holder { public: holder() : v() {}; holder( const std::vector<double>& in ) : v(in) {}; std::vector<double>& vector() { return v; }; const std::vector<double>& vector() const { return v; }; private: std::vector<double> v; }; class from_key { public: typedef holder result_type; from_key( const boost::unordered_map<std::string, holder >& m ) : map_(m) {}; const holder& operator() ( const std::string& in ) const { return map_.at(in); }; private: const boost::unordered_map<std::string, holder >& map_; }; typedef boost::transform_iterator<from_key, std::vector<std::string>::iterator > iterator; int main() { std::vector<std::string> keys; keys += "1","2","3"; std::vector<double> vals; vals += 1.0, 2.0, 3.0; holder h(vals); boost::unordered_map<std::string, holder > m; insert( m ) ( "1", h ) ( "2", h ) ( "3", h ); iterator it = boost::make_transform_iterator( keys.begin(), from_key( m ) ); iterator end = boost::make_transform_iterator( keys.begin(), from_key( m ) ); const std::vector<double>& v = it->vector(); std::for_each( vals.begin(), vals.end(), std::cout << bl::_1 << " " ); std::cout << std::endl; std::for_each( v.begin(), v.end(), std::cout << bl::_1 << " " ); std::cout << std::endl; }

2 1

[Interprocess]
by Daniel Neuberger 24 Jan '11

24 Jan '11

Hi Ion (and everyone else), I looked through the recent commits and it looks like support for XSI shared memory has been added (https:// svn.boost.org/trac/boost/changeset/67451) Does this mean XSI is ready to use now? Do you think these changes will make it into the upcoming 1.46 release? Alternatively, do you think applying the above changeset to Boost 1.43 be sufficient to be able to use XSI shared memory? Thanks again, - Daniel P.S. Sorry if anyone got another similar message to this from me; I sent one in response to another message but think the thread was already too old.

2 7

Random: How to get a different seed?
by Zoltán Lengyel 24 Jan '11

24 Jan '11

Hello, I am trying to make a simple program that can generate random integers in range, using boost::uniform_int. http://www.boost.org/doc/libs/1_45_0/doc/html/boost_random/tutorial.html#bo… This tutorial tells: "We use mt19937<http://www.boost.org/doc/libs/1_45_0/doc/html/boost/mt19937.html>with the default seed as a source of randomness. The numbers produced will be the same every time the program is run. One common method to change this is to seed with the current time (std::time(0) defined in ctime)." I have trouble getting this common method compile and work. Here's a tiny program that works, with the same seed at every run (like what the tutorial does), I have commented out my desperate tries to make the seed change. #include "uniform_int.hpp" #include "boost/random/variate_generator.hpp" #include "boost/random/mersenne_twister.hpp" #include <time.h> #include <iostream> using namespace std; using namespace boost; mt19937 gen; // time_t gen = time(0); int roll_die() { uniform_int<> dist(1, 6); variate_generator<mt19937&, uniform_int<> > die(gen, dist); //boost::variate_generator<time_t, boost::uniform_int<> > die(gen, dist); return die(); } int main() { for (int i = 0; i < 5; i++) cout << roll_die() << endl; return 0; } So, I would be glad, if someone could fix this for me, to have a different seed (depending on system time) at each start. Thanks!

5 7

[Preprocessor] Relative Addresses in BOOST_PP_FILENAME_1
by Hossein Haeri 24 Jan '11

24 Jan '11

Dear all, I am trying to use BOOST_PP_FILENAME_1 for a header file in my current directory. Unless I hardcode the full address, GCC 4.5.1 (MinGW32, WinXP, SP3) says it can't find the same file in which I am using BOOST_PP_FILENAME_1! Is there any way I can go for relative file names? I have already checked the following -- neither works for the same reasons: #define BOOST_PP_FILENAME_1 "./Header.hpp" //1 #define BOOST_PP_FILENAME_1 ".\Header.hpp" //2 #define BOOST_PP_FILENAME_1 "Header.hpp" //3 TIA, --Hossein

4 6

[statechart] (custom) state queries for asynchronous state machine
by Loek Cleophas 24 Jan '11

24 Jan '11

Hi, I'm trying to figure out how to perform (custom) state queries on statechart's asynchronous state machines. The tutorial at http://www.boost.org/doc/libs/1_44_0/libs/statechart/doc/tutorial.html#Stat… how to do this for synchronous state machines - using state_iterator and the state machine's state_begin() and state_end() member functions. However, for the asynchronous case, access to the state machine is via a scheduler only - and I don't see how to get the information from there nor is there any documentation on that in the tutorial. Any hints on how to do this? Regards, Loek

2 1

boost::trim throwing std::bad_cast exeption with custom basic_string
by Arash Abghari 24 Jan '11

24 Jan '11

Hi, I have a custom basic_string as follows: typedef basic_string<unsigned int> ustring; so if I pass an instance of ustring to boost:trim it throws an std::bad_cast exception. ustring str; boost::trim(str); The exception comes from here: include/boost/algorithm/string/detail/classification.hpp:45 return std::use_facet< std::ctype<CharT> >(m_Locale).is( m_Type, Ch ); It does not matter what character type I use for basic_string, It throws the exception for anything but char and wchar_t. Document mentions "A string is not restricted to std::basic_string and character does not have to be char or wchar_t, although these are most common candidates", So I assume, It must work with unsigned int or other types. Here is the system spec: boost: 1.40 gcc: 4.3.4 OS: Debian Lenny 64bit Thanks

3 7

Re: [Boost-users] [Fusion] Building parameter list for fusion::invoke
by Vivek 24 Jan '11

24 Jan '11

> > 2011/1/22 Vivek <vivek_at_[hidden]> > Or alternatively, is there a direct way to initialize a fusion vector? IIUC, its ctor just do the job, not? The problem is I don't know the arity or parameter types of the function being called. I just have a source of data (which can be simplified to TYPE data = data_source<TYPE>().pop();) and arbitrary functions being passed in. One alternative is to code-generate template specializations for a bunch of arity and use the constructor like you suggested. But I feel the "arity code generation" thing has been done so many times and so much better in boost that I should be able to use a transform or invoke function to take advantage of that. That's why I started trying to use fusion.

3 5

Re: [Boost-users] [Preprocessor] Relative Addresses in BOOST_PP_FILENAME_1
by Hossein Haeri 24 Jan '11

24 Jan '11

Hi TONGARI, > > #define BOOST_PP_FILENAME_1 "./Header.hpp" //1 > > #define BOOST_PP_FILENAME_1 ".\Header.hpp" //2 > > #define BOOST_PP_FILENAME_1 "Header.hpp" //3 > I have the same problem with you, I also use GCC 4.5.1, while <> works > fine but "" not. Strangely enough, <> doesn't work in my GCC either. (And, I'm not writing a precompiled header anyway.) Are you also using GCC under MinGW32? TIA, --Hossein

2 1

Help me out from boost.log
by Steven Woody 23 Jan '11

23 Jan '11

Hi, I want to use boost.log and I succeeded in building it with bjam with Visual Studio 2005. But I quickly found I cannot use it. Below code are from the tutorial, #include <boost/log/core.hpp> #include <boost/log/trivial.hpp> #include <boost/log/filters.hpp> logging::core::init_log_to_file( keywords::file_name = "dsttest_%N.log", keywords::rotation_size = 10 * 1024 * 1024, keywords::time_based_rotation = sinks::file::rotation_at_time_point(0, 0, 0), keywords::format = "[%TimeStamp%]: %_%" ); logging::core::get()->set_filter( flt::attr<logging::trivial::severity_level>("Severity") >= loggin::trivial::debug ); but the compiler (vc++ 8.0) just complains: error C2653: 'logging' : is not a class or namespace name error C2653: 'keywords' : is not a class or namespace name ... I tried to use boost::log::logging, but it did not help. Then I decided to try the most simple code: BOOST_LOG_TRIVIAL(debug) << "hello boost.log"; it passed the compiler but not the linker: libboost_log-vc80-mt-gd-1_45.lib(trivial.obj) : error LNK2019: unresolved external symbol "class boost::system::error_category const & __cdecl boost::system::generic_category(void)" (?generic_category@system@boost@@YAABVerror_category@12@XZ) referenced in function "void __cdecl boost::system::`dynamic initializer for 'posix_category''(void)" (??__Eposix_category@system@boost@@YAXXZ) .... Please help me! Thanks in advance. -- Life is the only flaw in an otherwise perfect nonexistence -- Schopenhauer narke public key at http://subkeys.pgp.net:11371 (narkewoody(a)gmail.com)

2 2