Calling subprocess with arguments

Mike Kazantsev mk.fraggod at
Fri Jun 19 11:21:42 EDT 2009

On Fri, 19 Jun 2009 08:07:29 -0700
Tyler Laing <trinioler at> wrote:

> I can't use communicate, as it waits for the child process to terminate.
> Basically it blocks. I'm trying to have dynamic communication between the
> python program, and vlc.

Unfortunately, subprocess module doesn't allow it out-of-the-box, but
you can use fnctl calls to perform non-blocking reads/writes on it's
pipes, like this:

  flags = fcntl.fcntl(fd, fcntl.F_GETFL)
  fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)

After that, you can grab all the available data from the pipe at any
given time w/o blocking.

Try this recipe:

Mike Kazantsev //
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