libtool's versioning system

Never try to set the interface numbers so that they correspond to the release number of
 your package. This is an abuse that only fosters misunderstanding of the purpose of library 
versions. Instead, use the -release flag (see Release numbers), but be warned that every release 
of your package will not be binary compatible with any other release.

文件明明就是這樣寫的... 可是 GNU/Linux 的軟體就是把 -version-info 當 -release 使用... 真是搞不懂啊... XD