How can I construct a subprocess call in Python for 2 or more commands for OS X or Linux?

Question

I would like to perform within a Python script the following: more 20151010_ABC.txt | grep QST > 20151010_ABC.txt.QST

for a number (almost a 1000 files) of such files.

Then,

to open within the script the VIM editor, passing on demand either *.txt or *.QST or NONE files as above.

Any ideas? Thank you!

Sample:

import subprocess
more = subprocess.Popen(['more', '20151010_AlterAeon.txt.prsd'], stdout=subprocess.PIPE,)
grep = subprocess.Popen(['grep', 'LVL'], stdin=more.stdout, stdout=subprocess.PIPE,)
feed = subprocess.Popen(['>', '20151010_AlterAeon.txt.prsd.LVL'], stdin=grep.stdout, stdout=subprocess.PIPE,)
end_of_pipe = feed.stdout
#print "Files:", end_of_pipe
for line in end_of_pipe:
    print line.strip()

Thank you @J.F.Sebastian for your guidance, as probably understood being a newbie here! — Paradigm, Oct 16 '15 at 09:09
related: [How do I use subprocess.Popen to connect multiple processes by pipes?](http://stackoverflow.com/q/295459/4279) — jfs, Oct 16 '15 at 09:12
is there a reason to use external processes here? You could emulate the pipeline in pure Python: `for line in file: if 'LVL' in line: output_file.write(line)` — jfs, Oct 16 '15 at 09:13
Thank you @J.F.Sebastian for the related comment. That solved (in a way) my question in a simple way. — Paradigm, Oct 16 '15 at 21:59

score 0 · Accepted Answer · answered Oct 16 '15 at 22:08

0

My question solved mainly based on the following:

result = subprocess.Popen('more 20151010_AlterAeon.txt.prsd | grep LVL >  
20151010_AlterAeon.txt.prsd.LVL',  
stdin=subprocess.PIPE, shell = True)

answered Oct 16 '15 at 22:08

Paradigm

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How can I construct a subprocess call in Python for 2 or more commands for OS X or Linux?

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