Is there any argument or options to setup a timeout for Python's subprocess.Popen method?
Something like this:
subprocess.Popen(['..'], ..., timeout=20)
?
I would advise taking a look at the Timer
class in the threading
module. I used it to implement a timeout for a Popen
.
First, create a callback:
def timeout( p ):
if p.poll() is None:
print 'Error: process taking too long to complete--terminating'
p.kill()
Then open the process:
proc = Popen( ... )
Then create a timer that will call the callback, passing the process to it.
t = threading.Timer( 10.0, timeout, [proc] )
t.start()
t.join()
Somewhere later in the program, you may want to add the line:
t.cancel()
Otherwise, the python program will keep running until the timer has finished running.
EDIT: I was advised that there is a race condition that the subprocess
p
may terminate between the p.poll()
and p.kill()
calls. I believe the following code can fix that:
import errno
def timeout( p ):
if p.poll() is None:
try:
p.kill()
print 'Error: process taking too long to complete--terminating'
except OSError as e:
if e.errno != errno.ESRCH:
raise
Though you may want to clean the exception handling to specifically handle just the particular exception that occurs when the subprocess has already terminated normally.