Get Variable value from .sh to Python

Question

I have an .sh file that produces a picture on Raspberry Pi. and inside this file I have the following:

Config.sh:

#!/bin/bash
suffix=$(date +%H%M%S)  
cd /home/pi/photobooth_images/  
sudo cp image1.jpg /usb/photobooth_images/image-${suffix}-1.jpg  
sudo convert -size 1800x1200 xc:white \  
        image1.jpg -geometry 1536x1152+240+24 -composite \   
    /home/pi/template/logo.png -geometry 192x1152+24+24 -composite \  
        PB_${suffix}.jpg  
sudo cp PB_${suffix}.jpg /usb/photobooth_montage/PB_${suffix}.jpg  
sudo rm /home/pi/photobooth_images/*  
returnvalue=PB_${suffix}.jpg  
echo "$returnvalue"

What I am trying to do here is get the PB_${suffix}.jpg "returnvalue" value (file name) it generated into Python. Now my Python program has this line, it runs the .sh file above.

Main.py:

return_value = subprocess.call("sudo ./" + config.sh, shell=True)  
print "The Value is: " + str(return_value) + " This value from Python"  

The output I get is this  
[08:33:02 04-10-2016] [PHOTO] Assembling pictures according to 1a template.  
PB_083302.jpg  
The Value is: 0 This value from Python  
The output I am expected should be something like "PB_070638.jpg"

Any help is greatly appreciated.

you shouldn't use `sudo` for simple operations like this. sudo is reserved for running administrative commands. — miraculixx, Apr 10 '16 at 13:01

idjaw · Accepted Answer · 2016-04-10T13:05:22.767

0

That is because subprocess.call only returns the return code of executing the script (documentation). You want the actual output of what your script returns, so you should be using check_output, and avoid using shell=True

subprocess.check_output(["sudo", "./", config.sh])

You also might want to revise running your script without root permission via sudo. It does not seem like something that should run using root privileges.

edited Apr 10 '16 at 13:05

answered Apr 10 '16 at 12:58

idjaw

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subprocess.check_output solved the issue, thank you very much. – Danny Constantine Apr 10 '16 at 14:03

score 0 · Answer 2 · edited May 23 '17 at 11:59

0

Try using the Popen constructor the with stdout arg:

subprocess.Popen(['"sudo ./" + config.sh'], stdout=subprocess.PIPE)

See also: Get return value from shell command in python

Also, here's more info on Popen in the Python docs. https://docs.python.org/2/library/subprocess.html#popen-constructor

edited May 23 '17 at 11:59

Community

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answered Apr 10 '16 at 12:59

Anthony E

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Get Variable value from .sh to Python

2 Answers2