Why is kill command not working on Openshot?

Question

I am using OpenShot version 1.4.3 in Ubuntu 14.04 (64 bit).

Here is my system details:

lsb_release -a:

    Distributor ID: Ubuntu
    Description:    Ubuntu 14.04.4 LTS
    Release:    14.04
    Codename:   trusty

uname -a:

    Linux 4.2.0-30-generic #36~14.04.1-Ubuntu SMP
    Fri Feb 26 18:49:23 UTC 2016
    x86_64 x86_64 x86_64 GNU/Linux

I opened openshot to edit my videos on Ubuntu 14.04. but when I tried to close it using kill(also tried pkill) command nothing happened. All other installed applications working properly as expected while trying to close them with kill command.

I even tried kill with sudo, but no use.

Why is kill not working on Openshot?
Is there any known bug is behind this problem in Ubuntu's Openshot implementation?

UPDATE :

As someone mentioned in comment , kill -9 is working properly. but why not kill is not working ?

Somebody may think it as a duplicate for kill and kill -9 commands. But my question is not about how to kill openshot.

My question is why is kill not working for openshot on Ubuntu?. So please ensure before marking my this as duplicate.

In particular, why is OpenShots not working properly with kill? Is its implementation itself is like that or because of any bug?

score 2 · Answer 1 · answered Apr 07 '16 at 13:37

When this happens, use the "show no mercy" option for kill:

kill -9 5772

Where 5772 is the pid of the application you want to kill.

Or you can kill by process name with:

pkill openshot

Or a slightly more complicated way of doing it. Find the pid and kill it in one line

pidof openshot | xargs kill -9

score 2 · Answer 2 · answered Apr 07 '16 at 14:31

kill sends a signal to the target process. Process can catch signals and handle them, except for the SIGKILL and SIGSTOP signals. If a process gets a signal which it is not prepared to handle, it dies. If it handles the signal, there is no guarantee that the process will die - it can do whatever it wants to. In other words, a simple kill <pid> is not guaranteed to kill the process.

In this case, OpenShot may be handling SIGTERM, the default signal that kill sends. Since SIGKILL cannot be handled, with kill -9 (which is the same as kill -KILL or kill -SIGKILL), OpenShot is terminated.

However, where possible, kill -9 should not be used. It gives the process no opportunity to clean up, so it may result in data loss/corruption. Try a plain kill first, and if it doesn't die after a reasonable interval, only then try kill -9/kill -KILL.

Why is kill command not working on Openshot?

2 Answers2