subprocess kill is failing while taking live logs

Question

#!/usr/bin/python
import subprocess
import signal
import time
p=subprocess("adb devices")
p_id=p.pid
time.sleep
os.kill(p_pid,signal.SIGINT)
print "bye"

This is working fine and printing "bye", but the below code is not terminating, keeps on printing log content, and won't print "bye".

#!/usr/bin/python
import subprocess
import signal
import time
p=subprocess("adb logcat -v time event")
p_id=p.pid
time.sleep
os.kill(p_pid,signal.SIGINT)
print "bye"

kindly suggest

Thanks in advance Bushra

Any particular reason you're using `os.kill()`, vs `p.kill()`? (The latter will correctly switch over to using `terminate()` when on Windows... on which point, could you specify your OS?) — Charles Duffy, May 23 '17 at 19:08
BTW, `time.sleep` doesn't do anything at all. Maybe you mean `time.sleep(1)` or such? — Charles Duffy, May 23 '17 at 19:10
BTW, which version of Python is this? I'd strongly suggest using the `timeout=` argument to `Popen()` if targeting 3.3 or later; that way you get the effect of `sleep()`, but automatically return early if the command exits before the timeout. — Charles Duffy, May 23 '17 at 19:18
(You may also find https://stackoverflow.com/questions/1191374/using-module-subprocess-with-timeout to be interesting). — Charles Duffy, May 23 '17 at 19:20

score 0 · Answer 1 · answered May 23 '17 at 19:15

#!/usr/bin/python
import subprocess
import time
p=subprocess.Popen(['adb', 'logcat', '-v', 'time', 'event'])
time.sleep(1) # wait for a second
p.kill()
print "bye"

Notable items:

If you use a shell, your signal is delivered to the shell, not the process it started. To ensure that the signal is delivered direct to the process, run the process directly.
time.sleep does absolutely nothing on its own; it needs to be called as a function, as in time.sleep(1), to have any effect.
Use p.kill() to let the subprocess module select the appropriate kill mechanism for the current platform, as opposed to os.kill().

subprocess kill is failing while taking live logs

1 Answers1