python equivalent of the following program

[AndyL]

Hi,

What would by a python equivalent of following shell program:

#!/bin/sh

prog1 > file1 &
prog2 > file2 &
As you see, I need to spawn a few processes and redirect stdout to some
files.

Thx,

A.

[blue99]

AndyL wrote:

Hi,

What would by a python equivalent of following shell program:

#!/bin/sh

prog1 > file1 &
prog2 > file2 &
As you see, I need to spawn a few processes and redirect stdout to some
files.

For example :

------------------cut here-------------------------------
#!/usr/bin/env python

import os

# 1-st variant

os.system("prog1 > tmp1.txt &")

# or 2-nd variant

os.popen("prog1 > tmp2.txt &")
---------------cut here-------------------------------------

Regards,
Rob

[Steven Bethard]

AndyL wrote:

What would by a python equivalent of following shell program:

#!/bin/sh

prog1 > file1 &
prog2 > file2 &

If you're just going for quick-and-dirty, Rob's suggestion of os.system
is probably a reasonable way to go. If you want better error reporting,
I suggest using open() and the subprocess module:

import subprocess

file1 = open('file1', 'w')
prog1 = subprocess.Popen(['prog1'], stdout=file1)

file2 = open('file2', 'w')
prog2 = subprocess.Popen(['prog2'], stdout=file2)

If at some point later you want to make sure that the processes
completed, you simply call .wait() on prog1 or prog2.

STeVe

[Edward Elliott]

Steven Bethard wrote:

import subprocess

file1 = open('file1', 'w')
prog1 = subprocess.Popen(['prog1'], stdout=file1)

And if the script runs somewhere that stderr is likely to disappear:

prog1 = subprocess.Popen(['prog1'], stdout=file1, stderr=subprocess.STDOUT)

[AndyL]

Edward Elliott wrote:

Steven Bethard wrote:

import subprocess

file1 = open('file1', 'w')
prog1 = subprocess.Popen(['prog1'], stdout=file1)

And if the script runs somewhere that stderr is likely to disappear:

prog1 = subprocess.Popen(['prog1'], stdout=file1, stderr=subprocess.STDOUT)

Forgot to mention before that the main motivation is to have the same
code on bot Linux and M$ platforms.
Does subprocess work well on both?

Also how to find out that the 'prog1' e.g. has exited and it is done?

Thx,
A.

[Edward Elliott]

AndyL wrote:

Edward Elliott wrote:

And if the script runs somewhere that stderr is likely to disappear:

prog1 = subprocess.Popen(['prog1'], stdout=file1,
stderr=subprocess.STDOUT)
Forgot to mention before that the main motivation is to have the same
code on bot Linux and M$ platforms.

Does subprocess work well on both?

yes

Also how to find out that the 'prog1' e.g. has exited and it is done?

prog1.wait() or prog1.poll(). look at the subprocess docs.

[AndyL]

Edward Elliott wrote:

AndyL wrote:

Edward Elliott wrote:

And if the script runs somewhere that stderr is likely to disappear:

prog1 = subprocess.Popen(['prog1'], stdout=file1,
stderr=subprocess.STDOUT)

Forgot to mention before that the main motivation is to have the same
code on bot Linux and M$ platforms.

Does subprocess work well on both?

yes

Also how to find out that the 'prog1' e.g. has exited and it is done?

prog1.wait() or prog1.poll(). look at the subprocess docs.

thx a lot.