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Max Boost Fusion tuple parameters
by Rodrigo Madera 15 Sep '13

15 Sep '13

Hello, What is the maximum Boost Fusion tuple param count? I was thinking of using it for about 200-300 elements. Anyone done this? I've heard of defines for this, but never actually *knew* of anyone actually doing it. Thanks, Rodrigo Madera

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Too many EOF's using boost::asio
by ustulation 13 Sep '13

13 Sep '13

I have a TCP server and client with following read and write functions: ----------------- Writes ---------------------- void SomeClass::startWrite() { //m_writeBuffer is boost::asio::streambuf..m_writeQueue is std::deque<std::string> m_writeBuffer.sputn(&m_writeQueue.at(0)[0], m_writeQueue.at(0).size()); //m_objStrandWrite is boost::asio::strand boost::asio::async_write( getSocket(), m_writeBuffer, m_objStrandWrite.wrap([this](const boost::system::error_code &e, std::size_t bytesTxd){writeHandler(e, bytesTxd);}) ); } void SomeClass::writeHandler(const boost::system::error_code &refErrorCode, std::size_t bytesTxd) { if(!m_bIsStopped) { m_writeQueue.pop_front(); if(refErrorCode) { if(refErrorCode != boost::asio::error::operation_aborted) { std::cerr << "Write Error: " << refErrorCode.message() << std::endl; stop(); } } else { if(!m_writeQueue.empty()) { startWrite(); } } } } ------------------- Reads ----------------- void SomeClass::startRead() { //m_readBuffer is boost::asio::streambuf..m_objStrandRead is boost::asio::strand boost::asio::async_read_until( getSocket(), m_readBuffer, m_szTermString, m_objStrandRead.wrap([this](const boost::system::error_code &e, std::size_t bytesRxd){readHandler(e, bytesRxd);}) ); } void SomeClass::readHandler(const boost::system::error_code &refErrorCode, std::size_t bytesRxd) { if(!m_bIsStopped) { if(refErrorCode) { if(refErrorCode != boost::asio::error::operation_aborted) { std::cerr << "Read error: " << refErrorCode.message() << std::endl; stop(); } } else { if(bytesRxd) { std::string szRxdData; szRxdData.resize(bytesRxd); m_readBuffer.sgetn(&szRxdData[0], bytesRxd); } startRead(); } } } I get very frequent End Of File (EOF) error on client's read. It is not always but frequent. I am running a threadpool by asking multiple std::threads to execute io_service::run() which never quits until io_service::stop() is called. The data given by the server is almost never more than 5MB. As you see in the code, for any error I call stop() which shuts down the connection gracefully. <Q> *Is there something wrong I'm doing because I see no reason for EOF error. Why should the server close/shutdown the connection?* The code does not do that explicitly. Anyway it is random - out of 10 times maybe 5 are successful reads and 5 become EOF's and I have to restart my client executable to connect again in each of those cases. Other sockets don't do that - eg., I've tested with QTcpSocket of Qt framework and it works all the time (no randomness). -- View this message in context: http://boost.2283326.n4.nabble.com/Too-many-EOF-s-using-boost-asio-tp465117… Sent from the Boost - Users mailing list archive at Nabble.com.

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using boost with net-snmp
by moshe levi 12 Sep '13

12 Sep '13

I wrote an example on how to integrate net-snmp with boost. please checkout http://blog-moshe.blogspot.co.il/

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ICMP Ping example running problem
by shunguang 12 Sep '13

12 Sep '13

Hi all, When i run *ping.cpp * at .\boost_1_53_0\doc\html\boost_asio\example\icmp, it comes with the error message: "Exception: open: An attempt was made to access a socket in a way forbidden by its access permissions". Debug shows that it comes from calling ",* socket_ (io_service , icmp::v4() )*" in the constructor. Google says the running computer must have administrator right, i do have it. i also checked my firewall settings, it looks fine to me also. Does anyone can give a help? Thanks, -shunguang -- View this message in context: http://boost.2283326.n4.nabble.com/ICMP-Ping-example-running-problem-tp4651… Sent from the Boost - Users mailing list archive at Nabble.com.

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[coroutine] help with code from docs
by Jeff Flinn 12 Sep '13

12 Sep '13

I'm trying to understand coroutine usage with boost 1.53.0. I'm getting an assertion when running the code snippet from the docs "Creating a coroutine" from http://www.boost.org/doc/libs/1_53_0/libs/coroutine/doc/html/coroutine/coro… #include <boost/coroutine/all.hpp> #include <string> typedef boost::coroutines::coroutine< int (std::string const&) > coro_t; // void f( boost::coroutine< std::string const&( int) > & ca) void f( coro_t::caller_type & ca) { std::string str( ca.get() ); // asserts here! ca(7); } int main(int argc, char* argv[]) { std::string str("abc"); coro_t c(f); c(str); // pass argument int res = c.get(); // returned value return 0; } Asserts in coroutine_get.hpp line 43: BOOST_ASSERT( static_cast< D const* >( this)->impl_->result_); Is the snippet from the doc incorrect or am I doing something else wrong. Thanks, Jeff

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boost::tr1::tuple or boost::tuple? how to compile the same code with both -std=c++98 and -std=c++11?
by Frédéric Bron 12 Sep '13

12 Sep '13

This small program compiles nicely with g++ 4.6.4 and -std=c++98 and boost 1.52.0: #include <iostream> #include <boost/math/tools/roots.hpp> #include <boost/tr1/tuple.hpp> std::tr1::tuple<double, double> f(double x) { return std::tr1::tuple<double, double>(x, 1.); } int main() { std::cout<<boost::math::tools::newton_raphson_iterate(f, 10., -9., +20., 10); return 0; } Now, I would like to be able to compile that program also with g++ 4.8.1 and -std=c++11 (I changed also boost to 1.53.0). If I do not change anything, std::tr1::tuple is replaced by std::tuple and I get the following error (see attached log): path/to/boost/include/boost/math/tools/roots.hpp:202:32: error: no match for 'operator=' (operand types are 'std::tuple<double&, double&>' and 'boost::fusion::tuple<double, double>') I tried to replace <boost/tr1/tuple.hpp> and std::tr1::tuple by <boost/tuple/tuple.hpp> and boost::tuple without any success. What should I do to have the same code compile with both -std=c++98 and -std=c++11? Regards, Frédéric

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Regex on Windows2012
by Michael Xanadu 11 Sep '13

11 Sep '13

Hi guys, I developed a little application called MyProgram.exe (Win7, VS2008 SP1, Qt 4.8.4) and a little DLL called MyLibrary.dll. The DLL uses BOOST's regex engine 1.5. The executable calls the DLL via couple of functions, one function inside the DLL uses the regex engine. I've tested the environment on Windows7 and all is OK. BUT: If I copy the application and the DLL to Windows2012 I see that the executable crashes if I use it. I took a closer look to the issue and found out that the cause for the crash seems to be the regex engine inside the DLL. If regex functions will be called inside the DLL, it crashes and also the application does. AND: The strange thing is, that this problem seems to occur only on Windows2012 and only if the regex engine is inside a DLL. If I use Windows7 instead or uses the regex engine inside an executable on Windows2012 - everything works fine. I've already tried a lot to solve the problem, including using different linking approaches (BOOST as shared DLL etc.). I wonder if anybody had similar issues or can give me a hint of what went wrong? Regards, Michael

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syntax error reporting from imported python modules
by Richi Lists 11 Sep '13

11 Sep '13

Hi, when I execute a python script that contains errors, I get nice and complete information from boost::python::error_already_set about the error and it's location. If the script that contains a syntax error is not executed directly, but imported from the main script, I don't get that exception. Instead it returns from the function as if everything was successful. When I check the result, the tasks from the other files were performed, just the stuff from the erroneous file is missing. Do I need to somehow attach the error reporting to the imported files? Rgds Richard

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[BOOST]BOOST_AUTO_TEST_CASE_TEMPLATE usage
by Hemanth Choudary M V (RBEI/ETA1) 11 Sep '13

11 Sep '13

Hi, In the code snippet below, The 3rd parameter in the BOOST_AUTO_TEST_CASE_TEMPLATE is a boost::mpl::list. Is the 3rd parameter restricted only to boost::mpl::list or anything else can also be used? #define BOOST_TEST_MODULE example #include <boost/test/included/unit_test.hpp> #include <boost/test/test_case_template.hpp> #include <boost/mpl/list.hpp> //____________________________________________________________________________// typedef boost::mpl::list<long long,unsigned char> test_types; BOOST_AUTO_TEST_CASE_TEMPLATE( my_test, T, test_types ) { BOOST_CHECK_EQUAL( sizeof(T), (unsigned)4 ); } //_ Mit freundlichen Grüßen / Best Regards, Hemanth Choudary MV RBEI/ETA1

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shared_ptr to this
by Gonzalo Garramuno 10 Sep '13

10 Sep '13

I have an application where I need to pass "this" in a callback belonging to a class to a function using a shared_ptr in another thread In code: struct Data { Data( void* p ) : ptr( p ) { } boost::shared_ptr<void> ptr; }; void threadA( Data* d ) { boost::shared_ptr<void> ptr( d->ptr ); delete d; // use ptr } class A { void init_thread() { Data* data = new Data( this ); boost.thread t( boost::bind( threadA, data ) ); } }; The problem is obvious. Once threadA closes, the shared ptr is destroyed as its count is 0 and as it points to the this of class A this gets deleted too. However my class A is still active and should not get deleted. How can I work around this?

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