1. To change the order of PATH items, you just need to put the newly-added path in front of the PATH, or at the back of the path to put it behind all the former PATH items.
2. Compile opencv on linux, this is a good helper: http://blog.sina.com.cn/s/blog_675e6b570101gpsj.html
3. Compile hdf5 on centos, a good helper is here: http://www.hdfgroup.org/ftp/HDF5/current/src/unpacked/release_docs/INSTALLAbout compiling some source code on centos
原文：http://www.cnblogs.com/huang-kun/p/4118355.html
