Michael Barton wrote:
> > subprocess.call([
> > "v.extract",
> > "input=%s" % os.getenv("GIS_OPT_INPUT"),
> > "output=%s_%s" % (os.getenv("GIS_OPT_OUTPUT"), i),
> > "type=point", "layer=1", "new=-1", "list=%s" % i])
>
> Glynn,
>
> How do subprocess.call and subprocess.Popen compare for running GRASS
> commands from inside Python scripts? Is call easier than Popen in this
> context?
subprocess.call is a convenience function for the simplest case where
you don't need to interact with the child process beyond waiting for
it to finish; it's defined as:
def call(*args, **kwargs):
"""Run command with arguments. Wait for command to complete, then
return the returncode attribute.
The arguments are the same as for the Popen constructor. Example:
retcode = call(["ls", "-l"])
"""
return Popen(*args, **kwargs).wait()
It behaves like system(), but without the shell (so you don't have to
deal with /bin/sh syntax vs cmd.exe syntax, spaces and other shell
metacharacters in argument values, etc).
It's roughly equivalent to os.spawnvp(P_WAIT,...), which is deprecated
in favour of the subprocess module. Most of the other os.* functions
are similarly deprecated, except for the os.exec* family (for which
the main use is executing g.parser).
--
Glynn Clements <[EMAIL PROTECTED]>
_______________________________________________
grass-dev mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/grass-dev
