平台:linux python :2.6+
linux下的命令行支持回答模式
Will execute a command, read the output and return it back.
param cmd: command to execute
param timeout: process timeout in seconds
param show: Display output to the front
param stdin_file: Enter the interactive information content of the file
return: a tuple of three: first stdout, then stderr, then exit code
raise OSError: on missing command or if a timeout was reached
example:
python shellCmd.py