Cannot pass an argument to python with "#!/usr/bin/env python"

Question

I needed to have a directly executable python script, so i started the file with #!/usr/bin/env python. However, I also need unbuffered output, so i tried #!/usr/bin/env python -u, but that fails with python -u: no such file or directory.

I found out that #/usr/bin/python -u works, but I need it to get the python in PATH to support virtual env environments.

What are my options?

Answer 1

In some environment, env doesn't split arguments. So your env is looking for python -u in your path. We can use sh to work around. Replace your shebang with the following code lines and everything will be fine.

#!/bin/sh ''''exec python -u -- "$0" ${1+"$@"} # ''' # vi: syntax=python 

p.s. we need not worry about the path to sh, right?

Answer 2

It is better to use environment variable to enable this. See python doc : http://docs.python.org/2/using/cmdline.html

for your case:

export PYTHONUNBUFFERED=1 script.py