i have install 1.43 version in my system,after use “./bjam install” to intall boost1.44,i met the following error.

[root@localhost gridcast]# g++ -o datetime datetime_tcp_async_server.cpp -lpthread -lboost_system -L/usr/local/lib

datetime_tcp_async_server.cpp:142:2: 警告：文件未以空白行结束

/tmp/ccjG0R2d.o: In function `__static_initialization_and_destruction_0(int, int)':

datetime_tcp_async_server.cpp:(.text+0x16c): undefined reference to `boost::system::get_system_category()'

datetime_tcp_async_server.cpp:(.text+0x176): undefined reference to `boost::system::get_generic_category()'

datetime_tcp_async_server.cpp:(.text+0x180): undefined reference to `boost::system::get_generic_category()'

datetime_tcp_async_server.cpp:(.text+0x18a): undefined reference to `boost::system::get_generic_category()'

datetime_tcp_async_server.cpp:(.text+0x194): undefined reference to `boost::system::get_system_category()'

/tmp/ccjG0R2d.o: In function `boost::asio::error::get_system_category()':

datetime_tcp_async_server.cpp:(.text._ZN5boost4asio5error19get_system_categoryEv[boost::asio::error::get_system_category()]+0x7): undefined reference to `boost::system::get_system_category()'

/tmp/ccjG0R2d.o: In function `boost::system::error_code::error_code()':

datetime_tcp_async_server.cpp:(.text._ZN5boost6system10error_codeC1Ev[boost::system::error_code::error_code()]+0x10): undefined reference to `boost::system::get_system_category()'

collect2: ld 返回 1

so i delete /usr/local/include/boost dir ,and rerun ”./bjam install”

-bash-3.2# g++ datetime_tcp_async_server.cpp -lpthread

datetime_tcp_async_server.cpp:142:2: warning: no newline at end of file

/tmp/ccQeKssV.o: In function `__static_initialization_and_destruction_0(int, int)':

datetime_tcp_async_server.cpp:(.text+0x176): undefined reference to `boost::system::generic_category()'

datetime_tcp_async_server.cpp:(.text+0x182): undefined reference to `boost::system::generic_category()'

datetime_tcp_async_server.cpp:(.text+0x18e): undefined reference to `boost::system::system_category()'

/tmp/ccQeKssV.o: In function `boost::system::get_system_category()':

datetime_tcp_async_server.cpp:(.text._ZN5boost6system19get_system_categoryEv[boost::system::get_system_category()]+0x5): undefined reference to `boost::system::system_category()'

/tmp/ccQeKssV.o: In function `boost::system::error_code::error_code()':

datetime_tcp_async_server.cpp:(.text._ZN5boost6system10error_codeC1Ev[boost::system::error_code::error_code()]+0x17): undefined reference to `boost::system::system_category()'

collect2: ld returned 1 exit status

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the name changed from `boost::system::get_generic_category()' to `boost::system::generic_category()',so it seems if i already have an old version of boost,i need remove it clearly to reinstall the new one by myself.