Trying to run an external program

[Brant Sears]

Hi. I'm new to Python and I am trying to use the latest release (2.5)
on Windows XP.

What I want to do is execute a program and have the results of the
execution assigned to a variable. According to the documentation the
way to do this is as follows:

import commands
x = commands.getsta tusoutput('dir' )

This should assign "x" to be the output of the command "dir".
However, when I run this (or any other command), x ends up being:

(1, "'{' is not recognized as an internal or external command,
\noperable program or batch file.")

From looking through the documentation, I'm believing that the
implementation of commands.getsta tusoutput is actually some multi-
step thing that starts with issuing the bracket character that is
being choked on. This leads me to believe that Python or perhaps just
the commands module is not setup correctly on my computer.

I installed Python using the Python2-5.msi link that I found at:

http://www.python.org/download/releases/2.5/

I left everything the default during installation, so Python was
installed to C:\Python25. The only other thing I did was add this
PATH variable on my computer.

Any ideas on what I might do to troubleshoot this?

Thanks!

Brant Sears

[Matimus]

Re: Trying to run an external program

Brant Sears wrote:

Hi. I'm new to Python and I am trying to use the latest release (2.5)
on Windows XP.
>
What I want to do is execute a program and have the results of the
execution assigned to a variable. According to the documentation the
way to do this is as follows:
>
import commands
x = commands.getsta tusoutput('dir' )
>
This should assign "x" to be the output of the command "dir".
However, when I run this (or any other command), x ends up being:
>
(1, "'{' is not recognized as an internal or external command,
\noperable program or batch file.")
>
From looking through the documentation, I'm believing that the
implementation of commands.getsta tusoutput is actually some multi-
step thing that starts with issuing the bracket character that is
being choked on. This leads me to believe that Python or perhaps just
the commands module is not setup correctly on my computer.
>
I installed Python using the Python2-5.msi link that I found at:

http://www.python.org/download/releases/2.5/

>
I left everything the default during installation, so Python was
installed to C:\Python25. The only other thing I did was add this
PATH variable on my computer.
>
Any ideas on what I might do to troubleshoot this?
>
Thanks!
>
Brant Sears

commands is a Unix module, hence it will not work in Windows XP. If you
don't need the return code try this:

import os

pipe = os.popen('dir')
x = pipe.read()
# do something with x

-Matt

[Stephan Kuhagen]

Re: Trying to run an external program

Brant Sears wrote:

Any ideas on what I might do to troubleshoot this?

As other stated out, you are using the wrong module. Try:

>>import os
>>p=os.popen('d ir')
>>for l in p:

.... print l
....
--- OUTPUT OF DIR HERE ---

>>p.close()

The return value of close is the return value of the command run. If you
need to read stdout and stderr of your command or write to its stdin, use
popen2, popen3, popen4 from the os-module.

Regards
Stephan

[Larry Bates]

Re: Trying to run an external program

Brant Sears wrote:

Hi. I'm new to Python and I am trying to use the latest release (2.5) on
Windows XP.
>
What I want to do is execute a program and have the results of the
execution assigned to a variable. According to the documentation the way
to do this is as follows:
>
import commands
x = commands.getsta tusoutput('dir' )
>
This should assign "x" to be the output of the command "dir". However,
when I run this (or any other command), x ends up being:
>
(1, "'{' is not recognized as an internal or external command,\nopera ble
program or batch file.")
>
From looking through the documentation, I'm believing that the
implementation of commands.getsta tusoutput is actually some multi-step
thing that starts with issuing the bracket character that is being
choked on. This leads me to believe that Python or perhaps just the
commands module is not setup correctly on my computer.
>
I installed Python using the Python2-5.msi link that I found at:

http://www.python.org/download/releases/2.5/

>
I left everything the default during installation, so Python was
installed to C:\Python25. The only other thing I did was add this PATH
variable on my computer.
>
Any ideas on what I might do to troubleshoot this?
>
Thanks!
>
Brant Sears

Others have answered your specific question, but on a more general note:

If you want directory information use os.listdir or glob.glob instead.
No reason to shell out to do a dir. If you were using dir as an example,
please disregard.

-Larry Bates

[Larry Bates]

Re: Trying to run an external program

Brant Sears wrote:

Hi. I'm new to Python and I am trying to use the latest release (2.5) on
Windows XP.
>
What I want to do is execute a program and have the results of the
execution assigned to a variable. According to the documentation the way
to do this is as follows:
>
import commands
x = commands.getsta tusoutput('dir' )
>
This should assign "x" to be the output of the command "dir". However,
when I run this (or any other command), x ends up being:
>
(1, "'{' is not recognized as an internal or external command,\nopera ble
program or batch file.")
>
From looking through the documentation, I'm believing that the
implementation of commands.getsta tusoutput is actually some multi-step
thing that starts with issuing the bracket character that is being
choked on. This leads me to believe that Python or perhaps just the
commands module is not setup correctly on my computer.
>
I installed Python using the Python2-5.msi link that I found at:

http://www.python.org/download/releases/2.5/

>
I left everything the default during installation, so Python was
installed to C:\Python25. The only other thing I did was add this PATH
variable on my computer.
>
Any ideas on what I might do to troubleshoot this?
>
Thanks!
>
Brant Sears

Others have answered your specific question, but on a more general note:

If you want directory information use os.listdir or glob.glob instead.
No reason to shell out to do a dir. If you were using dir as an example,
please disregard.

-Larry Bates