- Boost-users - lists.boost.org

Possibly too newbie a question?
by Eric Whitcombe 20 Mar '10

20 Mar '10

I haven't received any response to my question. If this is is not the appropriate forum I would appreciate some suggestions as to where to ask the question. I have gone over the mailing list groups page and this seems to be the place to ask it but I could be wrong. I am stepping through interprocess shared memory code and I was a little confused by the offset_ptr code that I was hitting*. I cannot figure out how that is specified to the template of rbtree_best_fit. I see in boost/interprocess/interprocess_fwd.hpp the declaration of managed_shared_memory by typedef'ing basic_managed_shared_memory with rbtree_best_fit<mutex_family> as the AllocationAlgorithm argument but I can't figure out how offset_ptr is is supplied as the VoidPointer argument to the rbtree_best_fit template. That template has 3 arguments but the forward declaration only provides one. Are the other two somehow inferred? If so, how? * I have looked at the documentation for interprocess - including the explanation of offset_ptr. I understand the need for it. I just don't see how it is incorporated into the rbtree_best_fit template.

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Re: [Boost-users] setup question
by Rick Boesch 20 Mar '10

20 Mar '10

Steven, many thanks. I tried your suggestion and was able to verify exactly what I needed to know. It seems "bjam -help" says -n will not execute the updating actions, but it says nothing about printing commands. I didn't cross check this with the Boost web page documentation which is in fact different (and says -n will print the commands). As for the email timestamp, blackouts from storms over the last few days, and a low battery on the box I sent the email from, apparently conspired to confuse the clock. Again, thanks for your help. Rick -----Original Message----- >From: Steven Watanabe <watanabesj(a)gmail.com> >Sent: Mar 19, 2010 6:56 PM >To: boost-users(a)lists.boost.org >Subject: Re: [Boost-users] setup question > >AMDG > >Rick Boesch wrote: >> Hello all -- looking for a small bit of guidance please. I'm building a 64bit Boost library from scratch. I'm fairly sure I did almost everything correctly, but would like to check one nagging detail. My system is Windows 7, Visual Studio 2005 and I'm building for 64 bit, specifically AMD64. >> >> I believe bjam.exe built correctly because my path was set up properly for the x64 toolset and bjam.exe was deposited in the auto-generated directory BOOST_ROOT\tools\jam\src\bin.ntx86_64. To do this, I ran "build vc8" on the command line. >> >> My question concerns the use of bjam along with the "using" instruction in the ...\V2\user-config.jam file. I set the "using" instruction to be >> >> using msvc : 8.0 : cl : <setup-amd64>vcvarsall ; >> >> and my command line is >> >> bjam address-model=64 --build-dir="C:\Program Files\boost\boost_1_42_0\boost-build" --build-type=complete stage >> >> I built two different ways: >> >> 1) In a virgin cmd window -- which is not set up for 64 bit tools by default -- I ran vcvarsall manually on the command line (with no args, I set it up to default to setting up 64 bit), which sets up my 64 bit environment and which I have echo to the screen "AMD64 env" for confirmation. I confirmed I was then defaulting to the correct "cl", etc., and then executed in BOOST_ROOT the bjam command line above. I have yet to test the output, but it seemed to work. >> >> 2) In another virgin cmd window, I cd'd to BOOST_ROOT and executed ONLY the bjam command line above. According to the documentation for the "using" instruction, the batch file vcvarsall (which is in my default PATH) is supposed to be called before any tools are used, but I never saw "AMD64 env" echoed to the screen, nor to a .log file which I piped to in order to make sure I didn't miss anything. Yet, bjam created an output tree containing various "address-model-64" directories. When I checked my PATH after the build, it did not contain the paths that vcvarsall is supposed to set up. >> > >The environment setup the Boost.Build does is local to each command. > >> Question: In scenario (2) above, vcvarsall clearly did not run in my cmd session, but did bjam run it in some internally generated shell? If no, why not (did I do something incorrectly)? If yes, is this why I didn't see my echo confirmation? > >You can run bjam -a -n <other options> to see the commands that >Boost.Build actually runs. > >> So I'm wondering if I have a 64 bit build or not -- and I prefer scenario (2) to scenario (1)! >> > >In Christ, >Steven Watanabe > >P.S. The timestamp on this message was 2004. >

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How to use scoped_lock
by weii 20 Mar '10

20 Mar '10

Dear all, I got a compiler(gcc 3.4.5) error while using boost.thread. The following is my code: ----------------------------------------------------------------------------------------------------------------------------- #include <boost/thread/thread.hpp> #include <boost/thread/mutex.hpp> #include <boost/bind.hpp> #include <iostream> boost::mutex io_mutex; void count(int id) { boost::mutex::scoped_lock lock(io_mutex,false); for (int i = 0; i < 10; ++i) { lock.lock(); std::cout << id << ": " << i << std::endl; lock.unlock(); } } int main(int argc, char* argv[]) { boost::thread thrd1(count, 1); boost::thread thrd2(count, 2); thrd1.join(); thrd2.join(); return 0; } ----------------------------------------------------------------------------- I know I can just abandon the lock() and unlock() function since the constructor and destructor will do them for me. But I can't understand how this error occurs and why the compiler has something to do with basic_timed_mutex. Anyone can give me some clues? Thanks in advance.

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Re: [Boost-users] Building boost-1.42.0 wuth VS 2005 - precompiled header error
by john blair 19 Mar '10

19 Mar '10

Thanks for the reply Paul. So this error has been discussed earlier http://lists.boost.org/boost-build/2009/08/22231.php Removing debug-store=database does work and like original poster I too am not sure what consequences that has. --- On Sat, 3/20/10, Paul A. Bristow <pbristow(a)hetp.u-net.com> wrote: > From: Paul A. Bristow <pbristow(a)hetp.u-net.com> > Subject: Re: [Boost-users] Building boost-1.42.0 wuth VS 2005 - precompiled header error > To: boost-users(a)lists.boost.org > Date: Saturday, March 20, 2010, 12:12 AM > > -----Original Message----- > > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] > On Behalf Of john blair > > Sent: Friday, March 19, 2010 2:13 AM > > To: Boost-users(a)lists.boost.org > > Subject: [Boost-users] Building boost-1.42.0 wuth VS > 2005 - precompiled header error > > > > I am trying to build boost-1.42.0 with visual studio > 2005 and getting the following error: > > assoc_laguerre.cpp > > libs\math\build\..\src\tr1\assoc_laguerre.cpp(6) : > error C2858: command-line opt > > ion 'program database name > (/Fdc:\toolchain\src\boost-1.42.0\build-win32-vc80-de > > > bug\boost\bin.v2\libs\math\build\msvc-8.0\dbg\dbg-str-dtbs\lnk-sttc\thrd-mlt\lib > > boost_math_tr1-vc80-mt-gd-1_42.pdb)' inconsistent with > precompiled header, which > > used > '/Fdc:\toolchain\src\boost-1.42.0\boost_1_42_0\vc80.pdb' > > libs\math\build\..\src\tr1\assoc_laguerre.cpp(6) : > error C2859: c:\toolchain\src > > > \boost-1.42.0\build-win32-vc80-debug\boost\bin.v2\libs\math\build\msvc-8.0\dbg\d > > > bg-str-dtbs\lnk-sttc\thrd-mlt\libboost_math_tr1-vc80-mt-gd-1_42.pdb > is not the p > > db file that was used when this precompiled header was > created, recreate the pre > > compiled header. > > ...failed updating 1 target... > > > > Anybody knows how to resolve this? > > John Maddock is the man who can definitively answer this, > but since he hasn't replied yet, > > does the > > I:\boost_1_42_0\libs\math\build\jamfile.v2 > > (re-build the pre-compiled header?) > > (cd to that directory and enter "bjam -a > > yourlogfile.log") > > do anything to help? > > Paul > > --- > Paul A. Bristow > Prizet Farmhouse > Kendal, UK LA8 8AB > +44 1539 561830, mobile +44 7714330204 > pbristow(a)hetp.u-net.com > > > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

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Re: [Boost-users] setup question
by Steven Watanabe 19 Mar '10

19 Mar '10

AMDG Rick Boesch wrote: > Hello all -- looking for a small bit of guidance please. I'm building a 64bit Boost library from scratch. I'm fairly sure I did almost everything correctly, but would like to check one nagging detail. My system is Windows 7, Visual Studio 2005 and I'm building for 64 bit, specifically AMD64. > > I believe bjam.exe built correctly because my path was set up properly for the x64 toolset and bjam.exe was deposited in the auto-generated directory BOOST_ROOT\tools\jam\src\bin.ntx86_64. To do this, I ran "build vc8" on the command line. > > My question concerns the use of bjam along with the "using" instruction in the ...\V2\user-config.jam file. I set the "using" instruction to be > > using msvc : 8.0 : cl : <setup-amd64>vcvarsall ; > > and my command line is > > bjam address-model=64 --build-dir="C:\Program Files\boost\boost_1_42_0\boost-build" --build-type=complete stage > > I built two different ways: > > 1) In a virgin cmd window -- which is not set up for 64 bit tools by default -- I ran vcvarsall manually on the command line (with no args, I set it up to default to setting up 64 bit), which sets up my 64 bit environment and which I have echo to the screen "AMD64 env" for confirmation. I confirmed I was then defaulting to the correct "cl", etc., and then executed in BOOST_ROOT the bjam command line above. I have yet to test the output, but it seemed to work. > > 2) In another virgin cmd window, I cd'd to BOOST_ROOT and executed ONLY the bjam command line above. According to the documentation for the "using" instruction, the batch file vcvarsall (which is in my default PATH) is supposed to be called before any tools are used, but I never saw "AMD64 env" echoed to the screen, nor to a .log file which I piped to in order to make sure I didn't miss anything. Yet, bjam created an output tree containing various "address-model-64" directories. When I checked my PATH after the build, it did not contain the paths that vcvarsall is supposed to set up. > The environment setup the Boost.Build does is local to each command. > Question: In scenario (2) above, vcvarsall clearly did not run in my cmd session, but did bjam run it in some internally generated shell? If no, why not (did I do something incorrectly)? If yes, is this why I didn't see my echo confirmation? You can run bjam -a -n <other options> to see the commands that Boost.Build actually runs. > So I'm wondering if I have a 64 bit build or not -- and I prefer scenario (2) to scenario (1)! > In Christ, Steven Watanabe P.S. The timestamp on this message was 2004.

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custom allocators Re:pool_alloc
by B Hart 19 Mar '10

19 Mar '10

I am not understanding the use of pool with std::set. i.e. the release_memory() function referenced in last example shown on: http://www.boost.org/doc/libs/1_42_0/libs/pool/doc/interfaces.html seems to do nothing. I call GetProcessMemoryInfo() and don't see any change after the set has gone out of scope. maybe someone could relate what happens to the allocated memory when set goes out of scope and release_memory() isn't called versus what happens when set goes out of scope and release_memory() is called. I want to do something like: 1.std::set<unsigned int, std::less<unsigned int>, boost::pool_allocator<unsigned int>> v; 2. for(int i=0; i<(K); i++) { v.insert(i); } 3. use v 4. release_memory() on v //dump all set elements in one action. Note, without custom allocator this is very slow for large sets. 5. repeat 1-4 with a new set

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[interprocesss] managed_mapped_file mutex question
by Andy Wiese 19 Mar '10

19 Mar '10

This is a somewhat different take on the question I asked earlier about interprocess mutexes in allocators. I am using a default interprocess::managed_mapped_file to hold a index for a multiprocess property store. There is one object named "index" in the mapped file, which is an interprocess::map. The map holds an interprocess::set of fixed-length strings. (I had an allocation problem with sets of string objects, but that's another topic) Many processes will both read and write this index map. Do the interprocess:: containers provide the needed synchronization, or do I need other synchronization mechanisms? If I am reading the docs correctly, it seems to say that I don't need additional synchronization if I am not adding/removing named objects. However, my tests break with multiple processes. I don't know if I just need my own synchronization or if a deeper problem is implied. Following is the simple test I have been using. Works with one process, breaks with two concurrent. (os-x 10.5, boost trunk) Thanks in advance for any advice! Andy ------------------------------------------------------- namespace bip = boost::interprocess; typedef struct { char t[64]; } thing_t; struct ThingLess { bool operator()(thing_t const & lhs, thing_t const & rhs) const { return (strcmp(lhs.t, rhs.t) < 0); } }; typedef bip::managed_mapped_file shared_store_t; typedef shared_store_t::segment_manager segment_manager_t; typedef bip::allocator<void, segment_manager_t> void_allocator_t; typedef bip::allocator<char, segment_manager_t> char_allocator_t; typedef bip::basic_string<char, std::char_traits<char>, char_allocator_t> char_string_t; typedef bip::allocator<char_string_t, segment_manager_t> char_string_allocator_t; typedef bip::allocator<thing_t, segment_manager_t> thing_allocator_t; typedef bip::set<thing_t, ThingLess, thing_allocator_t> thing_set_t; typedef std::pair<const char_string_t, thing_set_t> map_value_t; typedef bip::allocator<map_value_t, segment_manager_t> map_value_allocator_t; typedef bip::map< char_string_t, thing_set_t, std::less<char_string_t>, map_value_allocator_t> index_map_t; int main(int argc, char* argv[]) { //fork(); // forking here will usually cause a bus error int pid = getpid(); // find or create the mapped file std::auto_ptr<shared_store_t> store(new shared_store_t(bip::open_or_create, "/tmp/testindex", 1024*1024)); void_allocator_t allocator(store->get_segment_manager()); // find or create the index object index_map_t* index = store->get_segment_manager()- >find<index_map_t>("index").first; if (!index) { index = store->construct<index_map_t>("index") (std::less<char_string_t>(), allocator); assert(index); } // add pairs to the map, find them, remove them. for (int j=0; j<1000; ++j) { for (int i=0; i<100; ++i) { try { std::ostringstream ks; ks << "key" << i; std::ostringstream ts; ts << "thing" << i; // look for thing in map char_string_t key(ks.str().c_str(), allocator); index_map_t::iterator foundIt = index->find(key); if (foundIt == index->end()) { // add thing to map thing_t thing; strcpy(thing.t,ts.str().c_str()); thing_set_t thingSet(ThingLess(), allocator); thingSet.insert(thing); map_value_t entry(key,thingSet); index->insert(entry); std::cout << pid << " Added " << key << std::endl; } // look again... foundIt = index->find(key); if (foundIt != index->end()) { if (ts.str() == foundIt->second.begin()->t) { std::cout << pid << " FOUND " << key << ":"<< foundIt- >second.begin()->t << std::endl; } else { std::cout << pid << " FAILED? " << key << ":"<< foundIt- >second.begin()->t << std::endl; } } if (j%2) { // erase thing from map, every other pass just for some variety index->erase(key); std::cout << pid << " Erased " << key << std::endl; } } catch( bip::bad_alloc & ba ) { std::cout << "bad_alloc at " << j<<","<<i<< " "<< ba.what() << std::endl; } catch(std::exception & e) { std::cout << e.what() << std::endl; } catch(...) { std::cout << "some other exception" << std::endl; } } std::cout << pid << " --------- End Round " << j << " --------- " <<std::endl; } return 0; }

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[proto] generation of adaptive precision floating-point geometric predicates
by Andrew Durward 19 Mar '10

19 Mar '10

Hi all, I'm exploring the possibility of using proto to transform an expression (at compile time) into a sequence of terms whose sum represents an increasingly accurate floating-point approximation of the result. The underlying idea is based on a paper by Shewchuk [1]. The central concept is that for any expression (a # b) where # is {+, -, *}, the result can be expressed as (x + y) where x is the floating-point approximation of (a # b), and y is an error term whose value can also be computed as a floating-point value. In toying with proto, I've been able to transform simple expressions successfully but I can't seem to figure out how to define a grammar that will handle arbitrary combinations of {+, -, *} recursively. Here's what I've got so far: struct sum_approx{/* */}; struct sum_error{/* */}; struct diff_approx{/* */}; struct diff_error{/* */}; struct prod_approx{/* */}; struct prod_error{/* */}; struct Transform : proto::or_< proto::when< proto::plus< proto::terminal< _ >, proto::terminal< _ > > , fusion::cons< proto::_make_function( sum_approx() , proto::_left , proto::_right ) , fusion::cons< proto::_make_function( sum_error() , proto::_left , proto::_right ) > >() > // ... similar substitutions for minus and multiplies > {}; So the expression (a + b) yields the sequence: sum_approx(a,b) sum_error(a,b) Here's where I'm stuck. In the case of the expression (a + b)*(c - d), the addition and subtraction should be replaced by the appropriate sequences before the multiplication gets expanded to yield the final sequence: prod_approx( sum_approx(a,b), diff_approx(c,d) ) prod_error( sum_approx(a,b), diff_approx(c,d) ) prod_approx( sum_approx(a,b), diff_error(c,d) ) prod_error( sum_approx(a,b), diff_error(c,d) ) prod_approx( sum_error(a,b), diff_approx(c,d) ) prod_error( sum_error(a,b), diff_approx(c,d) ) prod_approx( sum_error(a,b), diff_error(c,d) ) prod_error( sum_error(a,b), diff_error(c,d) ) Obviously I need a recursive transform here but I'm not sure how to pass it the sequences generated by both the left and right subtrees. struct Transform : proto::or_< // ... as before , proto::when< proto::multiplies< Transform, Transform > , /* WHAT_GOES_HERE */< Transform( proto::_left ) , Transform( proto::_right ) > > > {}; What exactly do I need here? A metafunction to generate the proper sequence? What's the proper syntax to invoke it? Can anybody point me in the right direction? Thanks for any help, andrew [1] Shewchuk, Jonathon. Robust Adaptive Floating-Point Geometric Predicates. http://www.cs.cmu.edu/afs/cs/project/quake/public/papers/robust-predicates.p s

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Building boost-1.42.0 wuth VS 2005 - precompiled header error
by john blair 19 Mar '10

19 Mar '10

I am trying to build boost-1.42.0 with visual studio 2005 and getting the following error: assoc_laguerre.cpp libs\math\build\..\src\tr1\assoc_laguerre.cpp(6) : error C2858: command-line opt ion 'program database name (/Fdc:\toolchain\src\boost-1.42.0\build-win32-vc80-de bug\boost\bin.v2\libs\math\build\msvc-8.0\dbg\dbg-str-dtbs\lnk-sttc\thrd-mlt\lib boost_math_tr1-vc80-mt-gd-1_42.pdb)' inconsistent with precompiled header, which used '/Fdc:\toolchain\src\boost-1.42.0\boost_1_42_0\vc80.pdb' libs\math\build\..\src\tr1\assoc_laguerre.cpp(6) : error C2859: c:\toolchain\src \boost-1.42.0\build-win32-vc80-debug\boost\bin.v2\libs\math\build\msvc-8.0\dbg\d bg-str-dtbs\lnk-sttc\thrd-mlt\libboost_math_tr1-vc80-mt-gd-1_42.pdb is not the p db file that was used when this precompiled header was created, recreate the pre compiled header. ...failed updating 1 target... Anybody knows how to resolve this?

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Link issue with condition_variable
by Bradley W. Settlemyer 19 Mar '10

19 Mar '10

Hello, I'm using boost for the first time and I'm struggling to link my program. I've added libboost_pthread-mt to the link link (which got most of the symbols), but I still can't seem to get the symbols for the condition variables. The issue could be with the code, as I find the lock-mutex-condition_variable interactions to be very confusing, but it does appear to be a link issue. Consider the following error message emitted during link command: mpicxx <objects> -D_FILE_OFFSET_BITS=64 -L/lib64 -lfuse -lrt -ldl -lboost_thread-mt -lpthread -o aio_benchmark src/aio/thread_pool_adaptive_writer.o: In function `aio::ThreadPoolWriter::Write(aio::File*, std::vector<int, std::allocator<int> >, void*, unsigned long)': /home/bws/sandbox/aiofs/src/aio/thread_pool_writer.cc:59: undefined reference to `boost::condition_variable::notify_all()' /home/bws/sandbox/aiofs/src/aio/thread_pool_writer.cc:63: undefined reference to `boost::condition_variable::wait(boost::unique_lock<boost::mutex>&)' src/aio/thread_pool_writer.o: In function `aio::ThreadPoolWriter::threadWait()': /home/bws/sandbox/aiofs/src/aio/thread_pool_writer.cc:76: undefined reference to `boost::condition_variable::wait(boost::unique_lock<boost::mutex>&)' /home/bws/sandbox/aiofs/src/aio/thread_pool_writer.cc:110: undefined reference to `boost::condition_variable::notify_one()' Is condition variable in a different library? I am using the boost stuff distributed with Fedora 11: boost-1.37.0-7.fc11.x86_64 boost-devel-1.37.0-7.fc11.x86_64 Cheers, Brad

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