return value from python script to shell script

Question

I am new in Python. I am creating a Python script that returns a string "hello world." And I am creating a shell script. I am adding a call from the shell to a Python script.

1. i need to pass arguments from the shell to Python.
2. i need to print the value returned from Python in the shell script.

This is my code:

shellscript1.sh

#!/bin/bash
# script for testing
clear
echo "............script started............"
sleep 1
python python/pythonScript1.py
exit

pythonScript1.py

#!/usr/bin/python
import sys
print "Starting python script!"
try:
 sys.exit('helloWorld1') 
except:
 sys.exit('helloWorld2') 

Answer 1

You can't return message as exit code, only numbers. In bash it can accessible via $?. Also you can use sys.argv to access code parameters:

import sys
if sys.argv[1]=='hi':
 print 'Salaam'
sys.exit(0)

in shell:

#!/bin/bash
# script for tesing
clear
echo "............script started............"
sleep 1
result=`python python/pythonScript1.py "hi"`
if [ "$result" == "Salaam" ]; then
 echo "script return correct response"
fi

• Abdul Manaf: thanks ali. this code is working fine. but i need to return a string value. how it will be possible?
• Ali Nikneshan: you should capture python result: a=`python python/pythonScript1.py "test"``; echo $a will print what you print in python code
• zhangboyu: In my case, sys.exit(0) doesn't return anything and the shell script stops as well. But print(0) works well. What happens in my case?
• Ali Nikneshan: @zhangboyu , I guess you use ' instead of `
• zhangboyu: @AliNikneshan I really used `

Answer 2

Pass command line arguments to shell script to Python like this:

python script.py 1ドル 2ドル 3ドル

Print the return code like this:

echo $?

Answer 3

You can also use exit() without sys; one less thing to import. Here's an example:

$ python
>>> exit(1)
$ echo $?
1
$ python
>>> exit(0)
$ echo $?
0

• bgrupczy: The exit() is defined in site.py and it works only if the site module is imported so it should be used in the interpreter only. scaler.com/topics/exit-in-python geeksforgeeks.org/…