launching something within python

Question

Ok so as you can see to my question I'm a total newb at python. I'm building a python script and basically I want it to execute this line


/Library/Frameworks/GDAL.framework/Programs/ogr2ogr -f "GeoJSON" output.json input.shp

How do I get python to execute this as if I was typing it in my terminal?
Thanks

Why was this question down voted? Is it not good enough for stack overflow standards? — climboid, Feb 18 '13 at 20:32
I didn't downvote, but my guess is that it's because it's a duplicate of previous stack overflow questions like [this one](http://stackoverflow.com/questions/450285/executing-command-line-programs-from-within-python), which could easily be found by (for example) googling "launch command line Python" — David Robinson, Feb 18 '13 at 20:52

score 6 · Accepted Answer · answered Feb 18 '13 at 19:46

6

import os
os.system('/Library/Frameworks/GDAL.framework/Programs/ogr2ogr -f "GeoJSON" output.json input.shp')

More recently, it is recommended to use the subprocess package:

subprocess.call(['/Library/Frameworks/GDAL.framework/Programs/ogr2ogr', '-f',
                 '"GeoJSON"', 'output.json', 'input.shp'])

answered Feb 18 '13 at 19:46

David Robinson

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btw. does python wait for the execution to finish or just fork the process to the os? – thomas Feb 18 '13 at 19:48
1

@tomasz: `os.system` waits for it to finish. If you want to fork the process, use [subprocess.Popen](http://docs.python.org/2/library/subprocess.html). – David Robinson Feb 18 '13 at 19:48
Thanks David! I can accept your anser in exactly 9 minutes =) – climboid Feb 18 '13 at 19:52

score 2 · Answer 2 · answered Feb 18 '13 at 19:54

I cannot comment, but would like to add to the above answer:
The subprocess package allows for a return handle by which you can determine if the command was executed successfully. This may be important later in your script:

import subprocess  
COMMAND = '/Library/Frameworks/GDAL.framework/Programs/ogr2ogr -f "GeoJSON" output.json input.shp'  
return_code = subprocess.call(COMMAND, shell=True)

launching something within python

2 Answers2