Linux下动态链接库默认后缀是so，大部分的系统的动态链接库文件在以下目录：
/lib /usr/lib /usr/local/lib
If you ever happen to want to link against installed libraries
in a given directory, LIBDIR, you must either use libtool, and
specify the full pathname of the library, or use the `-LLIBDIR’
flag during linking and do at least one of the following:
- add LIBDIR to the `LD_LIBRARY_PATH’ environment variable
during execution - add LIBDIR to the `LD_RUN_PATH’ environment variable
during linking - use the `-Wl,–rpath -Wl,LIBDIR’ linker flag
- have your system administrator add LIBDIR to `/etc/ld.so.conf’ and run ldconfig
See any operating system documentation about shared libraries for more information, such as the ld(1) and ld.so(8) manual pages.