Unexpected output using subprocess in Python
- by Vic
I am trying to run a shell command from within my Python (version 2.6.5) code, but it is generating different output than the same command run within the shell (bash):
bash:
~> ifconfig eth0 | sed -rn 's/inet addr:(([0-9]{1,3}\.){3}[0-9]{1,3}).*/\1/p' | sed 's/^[ \t]*//;s/[ \t]*$//'
192.168.1.10
Python:
>>> def get_ip():
... cmd_string = "ifconfig eth0 | sed -rn \'s/inet addr:(([0-9]{1,3}\.){3}[0-9]{1,3}).*/\1/p' | sed 's/^[ \t]*//;s/[ \t]*$//\'"
... process = subprocess.Popen(cmd_string, shell=True, stdout=subprocess.PIPE)
... out, err = process.communicate()
... return out
...
>>> get_ip()
'\x01\n'
My guess is that I need to escape the quotes somehow when running in python, but I am not sure how to go about this.
NOTE: I cannot install additional modules or update python on the machine that this code needs to be run on. It needs to work as-is with Python 2.6.5 and the standard library.
