Capture file descriptors while running an external program

[jfigueiras]

I have a problem with the module subprocess!

The problem is that the external software that I am running under
subprocess.Popen opens stdin, stdout, stderr, and other file descriptors to
write and read in the hard drive.

As many other programs...

I know how to capture stdin, stdout and stderr, what I cannot do is to capture
the other file-descriptors. Is there any way to wrap those non-standard file
descriptors and make them write and read from a specific object that I define?
I know that I can use tmp files to do that, but i would like something running
without tmp files.

I'm not sure what you mean by "non-standard file descriptors". The
other program is free to open, read, write, etc any file he wants -
are you trying to trap any file operation it may want to do?
You *could* do such things -google for "code injection" and "API
hooking"- but I doubt it's what you really want.

--
Gabriel Genellina
Softlab SRL

Hi Gabriel!

When I wrote "non-standard file descriptors", I meant the file descriptior which
are pointed to files in the hardrive.
What I would like to do is not to trap any file operation, but instead intercept
that file operation, i.e. I would like the output of the external program to
don't be writen in a file (its normal behavior), but instead be sent to any
variable in my program.
I know the name of the file where the external program will write the output.. I
pass its name along the command line.

Joao Figueiras

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[Dennis Lee Bieber]

Please learn to trim your replies... Your client quoted the original
a signature block (without prefacing any quoting indicators), and your
response is written completely UNDER that quoted signature. Many clients
are designed to NOT quote signature blocks (ie, they stop quoting when
they see "\n-- \n"). I had to play tricks with cut&paste to get your
reply quoted...

I know the name of the file where the external program will write the output. I
pass its name along the command line.

If the OS permits, define a named pipe that the external program
will write to, supply that name as the "output file name", and then open
that same named pipe for reading in your program.
--
Wulfraed Dennis Lee Bieber KD6MOG
(e-mail address removed) (e-mail address removed)
HTTP://wlfraed.home.netcom.com/
(Bestiaria Support Staff: (e-mail address removed))
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