Give input to a python script from a shell?

Question

I'm trying to write a shell script that will run a python file that takes in some raw input. The python script is essentially along the lines of:

def main():
    name=raw_input("What's your name?")
    print "Hello, "+name
main()

I want the shell script to run the script and automatically feed input into it. I've seen plenty of ways to get shell input from what a python function returns, or how to run a shell from python with input, but not this way around. Basically, I just want something that does:

python hello.py
#  give the python script some input here
#  then continue on with the shell script.

`echo "read this!" | python hello.py` - what shell are we talking about anyway? — moooeeeep, Feb 19 '13 at 19:05
That looks like a UUOE (closely related to [UUOC](http://partmaps.org/era/unix/award.html)) — mgilson, Feb 19 '13 at 19:07
Also have a look at [this answer](http://stackoverflow.com/a/6271995/1025391) on automated testing and stdin input in Python. — moooeeeep, Feb 19 '13 at 19:20

score 8 · Accepted Answer · answered Feb 19 '13 at 19:01

8

Do you mean something like:

python hello.py <<EOF
Matt
EOF

This is known as a bash HERE document.

answered Feb 19 '13 at 19:01

mgilson

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score 4 · Answer 2 · answered Feb 19 '13 at 19:08

4

There's really no better way to give raw input than sys.stdin. It's cross platform too.

import sys
print "Hello {0}!".format(sys.stdin.read())

Then

echo "John" | python hello.py # From the shell
python hello.py < john.txt # From a file, maybe containing "John"

answered Feb 19 '13 at 19:08

Fredrick Brennan

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the second one is a useless use of cat ... `python hello.py < john.txt` – mgilson Feb 19 '13 at 19:09
@mgilson Indeed...old habits die hard. – Fredrick Brennan Feb 19 '13 at 19:10
I still do that (pretty frequently). – mgilson Feb 19 '13 at 19:11
I can't actually change the python files: I'm grading for an intro CS class, and they aren't teaching `sys`. I'm just trying to save myself time so I'm not giving manually input to 94 students' python scripts. – kip_price Feb 19 '13 at 19:12

Give input to a python script from a shell?

2 Answers2