Running a perl script in python and storing the output in a file

Question

I'm trying to run

script.pl < input > output

In python. I tried this:

subprocess.check_call(["script.pl","<","input",">","output"])

Which I guess is not the proper way to do it. Any help would be much appreciated!

ikegami · Accepted Answer · 2016-06-07 01:22:15Z

4

You want to execute the shell command

script.pl < input > output             # 0 args, redirects stdin and stdout

but you are executing the shell command

script.pl "<" input ">" output         # 4 args, and no redirections

If you want to run a shell command, you'll need to run a shell.

subprocess.check_call(["/bin/sh", "-c", "script.pl < input > output"])
  -or-
subprocess.check_call("script.pl < input > output", shell=True)

It would be best if you avoided running a shell at all.

in_fh  = open('input', 'r')
out_fh = open('output', 'w')
subprocess.check_call("script.pl", stdin=in_fh, stdout=out_fh)

answered Jun 6, 2016 at 16:20

ikegami

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1 Comment

Thanks! I used the in_fh and out_fh approach and it worked perfectly!

nehem · Accepted Answer · 2016-06-07 01:24:46Z

0

Keep it simple,

import os
os.system("script.pl < input > output")

answered Jun 7, 2016 at 1:24

nehem

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