basic command

GREP:

    search some process which 正在运行:

        ps -fe|grep "process_name" (fuzzy search)

    Kill process:

        kill -9 PID_num

    print the line and the file_name which included the "chars" in current directory:

        grep chars *file_name

        grep -r chars *file_name  (include sub directory)

        grep -r chars /var/log (in special directory and its sun directory)

        grep -v chars file_name (反向查找， 把不符合条件的找出来）

       grep -l chars file_name (only print file_name)

how to add package in ipython:

    import sys

    sys.path    (view current interpret path)

    sys.path.insert(0, 'package_path')