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Question

I am facing few problems while linking with boost libraries. I am trying to execute simple timer program

But when I execute the program getting below errors

~/boost_1_48_0/boost/asio/detail/impl/posix_tss_ptr.ipp:34: undefined reference to `pthread_key_create'
./timer.o: In function `~posix_tss_ptr': /~/boost_1_48_0/boost/asio/detail/posix_tss_ptr.hpp:48: undefined reference to `pthread_key_delete' 
./timer.o: In function `boost::asio::detail::posix_tss_ptr<boost::asio::detail::call_stack<boost::asio::detail::task_io_service, boost::asio::detail::task_io_service::thread_info>::context>::operator boost::asio::detail::call_stack<boost::asio::detail::task_io_service, boost::asio::detail::task_io_service::thread_info>::context*() const': ~/boost_1_48_0/boost/asio/detail/posix_tss_ptr.hpp:54: undefined reference to `pthread_getspecific'
./timer.o: In function `~posix_tss_ptr': ~/boost_1_48_0/boost/asio/detail/posix_tss_ptr.hpp:48: undefined reference to `pthread_key_delete' collect2: ld returned 1 exit status

I've included _I ~/boost_1_48_0/ -L ~/boost_1_48_0/stage/lib -lboost-system

Any quick pointers on this?

Answer 1

Did you remember to specify -pthread as well? From GCC manpage:

  -pthread Add support for multithreading using the POSIX threads library. This option sets flags for both the preprocessor and linker. 

It is required with code that uses POSIX threads.