spawn syntax + os.P_WAIT mode behavior + spawn stdout redirection

Derek Basch dbasch at
Thu Jan 20 19:20:09 EST 2005


*First question*

If the syntax of spawnl is:

spawnl(mode, path, ...)

Why does everyone write it like:

os.spawnlp(os.P_WAIT, 'cp', 'cp', 'index.html', '/dev/null')


os.spawnl(os.P_WAIT, "/var/www/db/smm/smm_train", "smm_train",

How is the first 'cp' a path to a file? why does the desired executable have to
be named again as the first parameter?

*Second question*

I have a script which calls another script using a spawn.

import os

os.spawnv(os.P_WAIT, "/var/www/db/cgi-bin/", ["python", ""])
#pid = os.spawnl(os.P_WAIT, 'sh', 'sh', '-cv', 'sleep 10; echo fark >

import time


I would expect that the script should take 10sec to return. However it
returns immediatly. Perhaps I am calling the script incorrectly?
Shouldn't it take 10sec to execute since the spawn mode argument is os.P_WAIT?

*Third question*

If I uncomment the second spawn call in I do not get any output to
/tmp/test.out and it also returns immediatly. Can anyone tell me why? 

Thank You Mighty Python Guru's,
Derek Basch

Do you Yahoo!? 
Yahoo! Mail - now with 250MB free storage. Learn more.

More information about the Python-list mailing list