Is this the right way to run a shell script inside Python?

Question

import subprocess retcode = subprocess.call(["/home/myuser/go.sh", "abc.txt", "xyz.txt"]) 

When I run these 2 lines, will I be doing exactly this?:

/home/myuser/go.sh abc.txt xyz.txt 

Why do I get this error? But when I run go.sh normally, I don't get that error.

File "/usr/lib/python2.6/subprocess.py", line 480, in call     return Popen(*popenargs, **kwargs).wait()   File "/usr/lib/python2.6/subprocess.py", line 633, in __init__     errread, errwrite)   File "/usr/lib/python2.6/subprocess.py", line 1139, in _execute_child     raise child_exception OSError: [Errno 8] Exec format error 

Answer 1

OSError: [Errno 8] Exec format error

This is an error reported by the operating system when trying to run /home/myuser/go.sh.

It looks to me like the shebang (#!) line of go.sh is not valid.

Here's a sample script that runs from the shell but not from Popen:

#\!/bin/sh echo "You've just called $0 $@." 

Removing the \ from the first line fixes the problem.

Answer 2

Change the code to following:

retcode = subprocess.call(["/home/myuser/go.sh", "abc.txt", "xyz.txt"], shell=True,) 

Notice "shell=True"

From: http://docs.python.org/library/subprocess.html#module-subprocess

On Unix, with shell=True: If args is a string, it specifies the command string to execute through the shell. This means that the string must be formatted exactly as it would be when typed at the shell prompt.