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Program_Options - Is there anyway to get the name of executable?
by asif saeed 10 Aug '11

10 Aug '11

Hi, Is it possible to get name of the executable that started the program using program_options? Thanks in advance, Asif

3 2

More problems with boost::asio and async_read
by Allan Nielsen 10 Aug '11

10 Aug '11

Hi I posted on this a couple of hours ago with some problems. It turned out that some of the problems I had might have been due to buggy hardware. But there is still some thing I do not understand... So, now I have reproduced some of of the problems I have with out any hardware (except from a PC). Basically I'm trying to read from a input source (in this case stdin) with a timeout. Due to the design of the existing application where this have to fit is it not possible to call run on my io_service. Here is my try so far: #include <boost/asio.hpp> #include <boost/bind.hpp> #include <boost/optional.hpp> using namespace std; void set_result( boost::optional<boost::system::error_code> * a, boost::system::error_code b ) { if( b == 0) a->reset( b ); } void receive(boost::asio::io_service & io, boost::asio::posix::stream_descriptor & stream, boost::asio::streambuf & result){ boost::optional<boost::system::error_code> timer_result; boost::optional<boost::system::error_code> read_result; boost::asio::deadline_timer timer( io ); timer.expires_from_now( boost::posix_time::milliseconds(5000) ); // allow up to 50ms of timeout for every char timer.async_wait( boost::bind(&set_result, &timer_result, _1) ); boost::asio::async_read( stream, result, boost::asio::transfer_at_least(1), boost::bind( &set_result, &read_result, _1 )); boost::system::error_code ec; while(1) { io.reset(); io.poll_one(ec); if ( read_result ) { timer.cancel(); return; } else if ( timer_result ) throw std::runtime_error("timeout"); } } void receive(boost::asio::io_service & io, boost::asio::posix::stream_descriptor & stream, size_t size, boost::asio::streambuf & result){ while( result.size() < size ) receive(io, stream, result); } int main(int argc, const char *argv[]) { boost::asio::io_service io; boost::asio::posix::stream_descriptor in(io, ::dup(STDIN_FILENO)); for(int i = 0; i < 5; i++){ std::cout << i << " Type in 4 chareters and press enter" << std::endl << std::endl; std::cout << "in> "; std::cout.flush(); try { boost::asio::streambuf buf; receive(io, in, 5, buf); std::cout << "out> "; std::copy(boost::asio::buffer_cast<const char *>(buf.data()), boost::asio::buffer_cast<const char *>(buf.data()) + buf.size(), ostream_iterator<char>(std::cout)); } catch (const std::exception & e) { std::cout << e.what() << endl; } } return 0; } At my first look, I thought that it was working, but after playing more around with the test app, I got some segmentations faults. I found that something bad happens if I wait for the first query to timeout, and then enter 5 chars the next. Here is what valgrind says: ==17848== Memcheck, a memory error detector ==17848== Copyright (C) 2002-2010, and GNU GPL'd, by Julian Seward et al. ==17848== Using Valgrind-3.6.1 and LibVEX; rerun with -h for copyright info ==17848== Command: ./ccTalkScan ==17848== ==17848== 0 Type in 4 chareters and press enter in> ==17848== Invalid read of size 8 ==17848== at 0x546EB4A: ??? (setcontext.S:60) ==17848== by 0x425847: receive(boost::asio::io_service&, boost::asio::posix::basic_stream_descriptor<boost::asio::posix::stream_descriptor_service>&, unsigned long, boost::asio::basic_streambuf<std::allocator<char> >&) (ccTalkScan.cxx:3 20) ==17848== by 0x425982: main (ccTalkScan.cxx:334) ==17848== Address 0x7feffdf68 is not stack'd, malloc'd or (recently) free'd ==17848== ==17848== Invalid read of size 8 ==17848== at 0x546EB52: ??? (setcontext.S:63) ==17848== by 0x425847: receive(boost::asio::io_service&, boost::asio::posix::basic_stream_descriptor<boost::asio::posix::stream_descriptor_service>&, unsigned long, boost::asio::basic_streambuf<std::allocator<char> >&) (ccTalkScan.cxx:3 20) ==17848== by 0x425982: main (ccTalkScan.cxx:334) ==17848== Address 0x7feffdf58 is not stack'd, malloc'd or (recently) free'd ==17848== ==17848== Invalid read of size 8 ==17848== at 0x546EB59: ??? (setcontext.S:64) ==17848== by 0x425847: receive(boost::asio::io_service&, boost::asio::posix::basic_stream_descriptor<boost::asio::posix::stream_descriptor_service>&, unsigned long, boost::asio::basic_streambuf<std::allocator<char> >&) (ccTalkScan.cxx:320) ==17848== by 0x425982: main (ccTalkScan.cxx:334) ==17848== Address 0x7feffdf28 is not stack'd, malloc'd or (recently) free'd ==17848== ==17848== Invalid read of size 8 ==17848== at 0x546EB4A: ??? (setcontext.S:60) ==17848== by 0x5E4BD2C: (below main) (in /lib64/libc-2.12.2.so) ==17848== Address 0x7feffdfd8 is not stack'd, malloc'd or (recently) free'd ==17848== ==17848== Invalid read of size 8 ==17848== at 0x546EB52: ??? (setcontext.S:63) ==17848== by 0x5E4BD2C: (below main) (in /lib64/libc-2.12.2.so) ==17848== Address 0x7feffdfc8 is not stack'd, malloc'd or (recently) free'd ==17848== ==17848== Invalid read of size 8 ==17848== at 0x546EB59: ??? (setcontext.S:64) ==17848== by 0x5E4BD2C: (below main) (in /lib64/libc-2.12.2.so) ==17848== Address 0x7feffdf98 is not stack'd, malloc'd or (recently) free'd ==17848== timeout 1 Type in 4 chareters and press enter in> asdf ==17848== Syscall param readv(vector[...]) points to unaddressable byte(s) ==17848== at 0x5EF7A81: readv (in /lib64/libc-2.12.2.so) ==17848== by 0x42AF1C: boost::asio::detail::descriptor_ops::non_blocking_read(int, iovec*, unsigned long, boost::system::error_code&, unsigned long&) (descriptor_ops.ipp:153) ==17848== by 0x4360BF: boost::asio::detail::descriptor_read_op_base<boost::asio::mutable_buffers_1>::do_perform(boost::asio::detail::reactor_op*) (descriptor_read_op.hpp:55) ==17848== by 0x427CE4: boost::asio::detail::reactor_op::perform() (reactor_op.hpp:40) ==17848== by 0x429003: boost::asio::detail::epoll_reactor::run(bool, boost::asio::detail::op_queue<boost::asio::detail::task_io_service_operation>&) (epoll_reactor.ipp:286) ==17848== by 0x429C81: boost::asio::detail::task_io_service::do_one(boost::asio::detail::scoped_lock<boost::asio::detail::posix_mutex>&, boost::asio::detail::task_io_service::idle_thread_info*) (task_io_service.ipp:264) ==17848== by 0x42986F: boost::asio::detail::task_io_service::poll_one(boost::system::error_code&) (task_io_service.ipp:188) ==17848== by 0x42A0C2: boost::asio::io_service::poll_one(boost::system::error_code&) (io_service.ipp:103) ==17848== by 0x4255E1: receive(boost::asio::io_service&, boost::asio::posix::basic_stream_descriptor<boost::asio::posix::stream_descriptor_service>&, boost::asio::basic_streambuf<std::allocator<char> >&) (ccTalkScan.cxx:307) ==17848== by 0x425847: receive(boost::asio::io_service&, boost::asio::posix::basic_stream_descriptor<boost::asio::posix::stream_descriptor_service>&, unsigned long, boost::asio::basic_streambuf<std::allocator<char> >&) (ccTalkScan.cxx:320) ==17848== by 0x425982: main (ccTalkScan.cxx:334) ==17848== Address 0x65ba4f0 is 0 bytes inside a block of size 512 free'd ==17848== at 0x4C25C4F: operator delete(void*) (vg_replace_malloc.c:387) ==17848== by 0x432D07: __gnu_cxx::new_allocator<char>::deallocate(char*, unsigned long) (new_allocator.h:95) ==17848== by 0x4316BF: std::_Vector_base<char, std::allocator<char> >::_M_deallocate(char*, unsigned long) (stl_vector.h:146) ==17848== by 0x42FD64: std::_Vector_base<char, std::allocator<char> >::~_Vector_base() (stl_vector.h:132) ==17848== by 0x42D6A4: std::vector<char, std::allocator<char> >::~vector() (stl_vector.h:313) ==17848== by 0x42B657: boost::asio::basic_streambuf<std::allocator<char> >::~basic_streambuf() (basic_streambuf.hpp:114) ==17848== by 0x425A77: main (ccTalkScan.cxx:336) ==17848== out> 2 Type in 4 chareters and press enter in> timeout 3 Type in 4 chareters and press enter in> timeout 4 Type in 4 chareters and press enter in> timeout ==17848== ==17848== HEAP SUMMARY: ==17848== in use at exit: 168 bytes in 3 blocks ==17848== total heap usage: 65 allocs, 62 frees, 22,246 bytes allocated ==17848== ==17848== LEAK SUMMARY: ==17848== definitely lost: 0 bytes in 0 blocks ==17848== indirectly lost: 0 bytes in 0 blocks ==17848== possibly lost: 0 bytes in 0 blocks ==17848== still reachable: 168 bytes in 3 blocks ==17848== suppressed: 0 bytes in 0 blocks ==17848== Rerun with --leak-check=full to see details of leaked memory ==17848== ==17848== For counts of detected and suppressed errors, rerun with: -v ==17848== Use --track-origins=yes to see where uninitialised values come from ==17848== ERROR SUMMARY: 27 errors from 9 contexts (suppressed: 4 from 4) I have tried different things to fix, but I that I might have mis understood a thing or two here. So some help would be most appreciated. -- Allan W. Nielsen

2 8

unlocatable infinite loop when using boost::serialization
by Griffin Howlett 10 Aug '11

10 Aug '11

Ok so i've set up boost::serialization to work with objects whose constructor and destructors are private (forcing you to make them through "factories"), but after doing the coming steps, the << operator of a boost::oarchive never returns. I've followed what was happening exactly in a debugger, but don't know what's happening *after the ending brackets of the object's serialization function. It's not even reaching the overloaded destroy function*. I think it's some internal business. - To do this i've overided the `load/save_construct_data function` and the `access::destroy template function` with the appropriate parameters. - I also defined a serialization function for each factory-built object, but it doesn't do anything as to force you to pass a pointer instead. - You'll also notice i've added my own Save() function as so the user can specify a different factory to use for recreating (loading) the object back up if needed. **Why would this be happening and how do i fix it?** here's the source: oa << WallBody2; //this is the call in main, wallBody2 is a b2Body* template<> static void access::destroy( const b2Body * t) // const appropriate here? { // the const business is an MSVC 6.0 hack that should be // benign on everything else const_cast<b2Body*>(t)->GetWorld()->DestroyBody(const_cast<b2Body*>(t)); } template<> static void access::destroy( const b2Fixture * t) // const appropriate here? { // the const business is an MSVC 6.0 hack that should be // benign on everything else const_cast<b2Fixture*>(t)->GetBody()->DestroyFixture(const_cast<b2Fixture*>(t)); } template<class Archive> inline void save_construct_data( Archive & ar, const b2Body * t, const unsigned int file_version) { // save data required to construct instance b2World* WorldPtr= const_cast<b2Body*>(t)->GetWorld(); ar & WorldPtr; Save(ar, const_cast<b2Body*>(t), file_version); } template<class Archive> inline void save_construct_data( Archive & ar, const b2Fixture * t, const unsigned int file_version) { // save data required to construct instance b2Body* BodyPtr= const_cast<b2Fixture*>(t)->GetBody(); ar & BodyPtr; Save(ar, const_cast<b2Fixture*>(t), file_version); } template<class Archive> void serialize(Archive & ar, b2Fixture& b2, const unsigned int version) { std::cout << "b2Fixture is not serializable, only b2Fixture pointers are" << std::endl;}; template<class Archive> void serialize(Archive & ar, b2Body& b2, const unsigned int version) { std::cout << "b2Fixture is not serializable, only b2Fixture pointers are" << std::endl;}; template<class Archive> void Save(Archive & ar, b2Body* b2, const unsigned int version) { b2World* World = b2->GetWorld(); ar & World; b2BodyDef InitialBodyDef; InitialBodyDef.inertiaScale= b2->GetInertia(); // QUESTION: Is there any way to get/set this from a body (not def) ar & InitialBodyDef; // QUESTION: wtf is inertiaScale? any relation to MassData? b2BodyDef BodyDef; BodyDef.angle= b2->GetAngle(); BodyDef.position= b2->GetPosition(); BodyDef.active= b2->IsActive(); BodyDef.angularDamping= b2->GetAngularDamping(); BodyDef.angularVelocity= b2->GetAngularVelocity(); BodyDef.awake= b2->IsAwake(); BodyDef.bullet= b2->IsBullet(); BodyDef.fixedRotation= b2->IsFixedRotation(); BodyDef.linearDamping= b2->GetLinearDamping(); BodyDef.linearVelocity= b2->GetLinearVelocity(); BodyDef.type= b2->GetType(); BodyDef.userData= b2->GetUserData(); ar & BodyDef; // number of fixtures saved first so when loaded we know // how many fixturedefs to extract unsigned int numbFixtures=0; for (b2Fixture* fixture = b2->GetFixtureList(); fixture; fixture = fixture->GetNext()) numbFixtures++; ar & numbFixtures; //TODO: find out if boost will detect this as a list for (b2Fixture* fixture = b2->GetFixtureList(); fixture; fixture = fixture->GetNext()) ar & fixture; } template<class Archive> void Save(Archive & ar, b2Fixture* b2, const unsigned int version) { b2Body* Body = b2->GetBody(); ar & Body; //Registered so boost can differentiate types of "shapes" ar.register_type(static_cast<b2CircleShape *>(NULL)); ar.register_type(static_cast<b2PolygonShape *>(NULL)); b2Shape* Shape= b2->GetShape(); ar & Shape; b2FixtureDef FixtureDef; FixtureDef.density= b2->GetDensity(); FixtureDef.filter= b2->GetFilterData(); FixtureDef.friction= b2->GetFriction(); FixtureDef.isSensor= b2->IsSensor(); FixtureDef.restitution= b2->GetRestitution(); FixtureDef.userData= b2->GetUserData(); ar & FixtureDef; }

1 0

Boost system library error
by Abbas Banaiyan 10 Aug '11

10 Aug '11

Hi, I installed Boost 1.4.47 on a Linux x86_64 server with gcc 4.4.4. When I try to make a simulator which uses Boost libraries I get the following error message: /home/abanaiya/local//include/boost/system/error_code.hpp:316: note: candidates are: boost::system::error_code::error_code(int&, const boost::system::error_category&) /home/abanaiya/local//include/boost/system/error_code.hpp:315: note: boost::system::error_code::error_code() /home/abanaiya/local//include/boost/system/error_code.hpp:311: note: boost::system::error_code::error_code(const boost::system::error_code&) ../../src/boost.task-0.4.2/boost/task/detail/bind_processor_linux.hpp: In function âvoid boost::this_thread::bind_to_processor(unsigned int)â: ../../src/boost.task-0.4.2/boost/task/detail/bind_processor_linux.hpp:41: error: no matching function for call to âboost::system::error_code::error_code(int&, const boost::system::error_category& (&)())â /home/abanaiya/local//include/boost/system/error_code.hpp:316: note: candidates are: boost::system::error_code::error_code(int&, const boost::system::error_category&) /home/abanaiya/local//include/boost/system/error_code.hpp:315: note: boost::system::error_code::error_code() /home/abanaiya/local//include/boost/system/error_code.hpp:311: note: boost::system::error_code::error_code(const boost::system::error_code&) ../../src/boost.task-0.4.2/boost/task/detail/bind_processor_linux.hpp: In function âvoid boost::this_thread::bind_to_any_processor()â: ../../src/boost.task-0.4.2/boost/task/detail/bind_processor_linux.hpp:59: error: no matching function for call to âboost::system::error_code::error_code(int&, const boost::system::error_category& (&)())â /home/abanaiya/local//include/boost/system/error_code.hpp:316: note: candidates are: boost::system::error_code::error_code(int&, const boost::system::error_category&) /home/abanaiya/local//include/boost/system/error_code.hpp:315: note: boost::system::error_code::error_code() /home/abanaiya/local//include/boost/system/error_code.hpp:311: note: boost::system::error_code::error_code(const boost::system::error_code&) /home/abanaiya/local//include/boost/system/error_code.hpp: At global scope: /home/abanaiya/local//include/boost/system/error_code.hpp:214: warning: âboost::system::posix_categoryâ defined but not used /home/abanaiya/local//include/boost/system/error_code.hpp:215: warning: âboost::system::errno_ecatâ defined but not used /home/abanaiya/local//include/boost/system/error_code.hpp:216: warning: âboost::system::native_ecatâ defined but not used make[2]: *** [sim.o] Error 1 make[1]: *** [all-recursive] Error 1 make: *** [all-recursive] Error 1 I also received the following error that I removed it by disabling the corresponded line at api_config.hpp file. /home/abanaiya/local//include/boost/system/api_config.hpp:28:5: error: #error user defined BOOST_POSIX_API or BOOST_WINDOWS_API not supported I also tried version 1.4.42 and got the same error. Would you please let me know hot to resolve it. I run the following command to install the Boost: ./bjam --prefix=$HOME/local install Thanks, Abbas

1 0

Public Encryption with ASIO SSL
by David McCallum 09 Aug '11

09 Aug '11

I'm trying to create a system where clients can encrypt messages, but only the server can decrypt them. I'm configuring the context on the server-side like so: context_.set_options(boost::asio::ssl::context::default_workarounds | boost::asio::ssl::context::no_sslv2); context_.set_password_callback(boost::bind(&server::get_password, this)); context_.use_private_key_file("server.pem", boost::asio::ssl::context::pem); However, I can't find any way to load the public key on the clients. Can I create a connection that relies on public-key encryption? Or do the SSL classes expect me to use public-key encryption only to generate symmetrical keys, ie with Diffie-Hellman? -David

1 0

Boost::Test Samples?
by Jeffrey Walton 09 Aug '11

09 Aug '11

Hi All, I'm not sure I have chosen the right testing architecture (external runner for a DSO), and I am having problems getting Boost::Test to run properly. I have print statements which are not printing in functions registered with BOOST_TEST_SUITE. And I have spiked a test would should print an error message. I thought it would be a good idea to look at [sample] projects that work rather than code snippets. Unfortunately, the link for "collection of examples" at [1] is broken. Does anyone know where to find Boost::Test samples? Thanks in advance, Jeff [1] http://www.boost.org/doc/libs/1_44_0/libs/test/doc/html/utf/intro.html

5 10

[mpl] Safe to instantiate mpl classes for tag-dispatch-by-instance?
by Gabriel Redner 09 Aug '11

09 Aug '11

Hi all, Say I have a functor which accepts a tag instance: struct tagA {}; struct tagB {}; struct MyFunc { template <typename TTag> void operator()(TTag, int other_stuff) {...} }; In some cases I want to pass multiple tags at once. Is it safe to just instantiate mpl::pair, mpl::vector, etc. and use them for this purpose, since from a runtime perspective they're just empty classes? Or, is this a Bad Idea for some reason? Thanks, -Gabe

1 0

Segmentation fault when using asio and poll_one
by Allan Nielsen 09 Aug '11

09 Aug '11

Hi I'm using Boost 1.46.1 asio for doing serial communication. About 1/1000 times when I run the poll_one I get this segmentation fault: Program received signal SIGSEGV, Segmentation fault. 0x0000000000434a7a in boost::asio::detail::reactor_op::perform (this=0x402010af1010004) at /usr/include/boost-1_46/boost/asio/detail/reactor_op.hpp:40 40 return perform_func_(this); (gdb) bt #0 0x0000000000434a7a in boost::asio::detail::reactor_op::perform (this=0x402010af1010004) at /usr/include/boost-1_46/boost/asio/detail/reactor_op.hpp:40 #1 0x0000000000435da6 in boost::asio::detail::epoll_reactor::run (this=0x6625c0, block=false, ops=...) at /usr/include/boost-1_46/boost/asio/detail/impl/epoll_reactor.ipp:286 #2 0x0000000000436a24 in boost::asio::detail::task_io_service::do_one (this=0x6624e0, lock=..., this_idle_thread=0x0) at /usr/include/boost-1_46/boost/asio/detail/impl/task_io_service.ipp:264 #3 0x0000000000436612 in boost::asio::detail::task_io_service::poll_one (this=0x6624e0, ec=...) at /usr/include/boost-1_46/boost/asio/detail/impl/task_io_service.ipp:188 #4 0x0000000000436e65 in boost::asio::io_service::poll_one (this=0x7fffffffe240, ec=...) at /usr/include/boost-1_46/boost/asio/impl/io_service.ipp:103 #5 0x000000000043b69b in CcTalkPort::receive (this=0x7fffffffe240) at /home/awn/git/gamblify/hardware/gmbio/software/test/ccTalkScan.cxx:382 #6 0x000000000043b7dc in CcTalkPort::receive (this=0x7fffffffe240, size=5) at /home/awn/git/gamblify/hardware/gmbio/software/test/ccTalkScan.cxx:396 #7 0x000000000043bcb5 in CcTalkPort::_ask (this=0x7fffffffe240, req=...) at /home/awn/git/gamblify/hardware/gmbio/software/test/ccTalkScan.cxx:411 #8 0x000000000043ac6e in CcTalkPort::ask (this=0x7fffffffe240, req=...) at /home/awn/git/gamblify/hardware/gmbio/software/test/ccTalkScan.cxx:317 #9 0x000000000043daef in CcTalkDevice::ask_hex (this=0x7fffffffe300, v=..., m=..., s=...) at /home/awn/git/gamblify/hardware/gmbio/software/test/ccTalkScan.cxx:583 #10 0x000000000043ce69 in CcTalkDevice::request_software_revision (this=0x7fffffffe300) at /home/awn/git/gamblify/hardware/gmbio/software/test/ccTalkScan.cxx:507 #11 0x000000000043c57f in CcTalkDevice::coreInfo (this=0x7fffffffe300) at /home/awn/git/gamblify/hardware/gmbio/software/test/ccTalkScan.cxx:459 #12 0x00000000004325ff in main (argc=1, argv=0x7fffffffe528) at /home/awn/git/gamblify/hardware/gmbio/software/test/ccTalkScan.cxx:820 Here is the snippet where I call it: while(1) { io_service.reset(); io_service.poll_one(ec); if ( read_result ) { timer.cancel(); return; } else if ( timer_result ) { throw CcTalkTimeOutException(); } } Any hints on how to debug this? -- Allan W. Nielsen

2 1

Working around the restriction in enable_shared_from_this
by kelvSYC 09 Aug '11

09 Aug '11

Suppose I have a class called Group, extending boost::enable_shared_from_this<Group>. Now suppose I have something like this: class Foo { boost::shared_ptr<const Group> G; public: Foo(const Group& G_) : G(G_.shared_from_this()) {} }; This would totally barf if, among other things, G_ was allocated from the stack, say, since I don't have an owning shared_ptr instance. So, it would appear that, at the very least, if you were to allocate a Group on the stack, then you would need a shared_ptr with a null deleter to make use of Foo. This seems inconvenient to whoever may want to use Foo, so is there a way to change this so get around the shared_ptr instance restriction without changing Foo?

1 0

path filesystem
by rudy 09 Aug '11

09 Aug '11

Hi, This is my first post, so please advise me if this is not the correct place to post my question. This is my question: I have the following directory pattern (Dir1 is the parent directory, and the rest are the child files/subdirectories): Dir1 file1 file2 .file3 subdir1 .subdir2 the following code will go through the Dir1, and it will fail in creating the "path" when it reaches ".file3" or ".subdir2" boost::filesystem:ath dir1_path(filepath.c_str()); How should I create a path to a directory that (for example) has the following path? /root/my_docs/pgg/.file1 filesystem::path works just fine if I had to deal with (/root/my_docs/pgg/file1) instead of (/root/my_docs/pgg/.file1) !!! apparently when the file/directory starts with '.', I cannot get filesystem::path to behave properly. please advise, thanks, Rudy

1 0