杀死bash和子进程

Question

My C program executes commands in a bash shell. To do this, I fork and in the child process I run:

char* command = "..."; /* provided by user */
execlp("/bin/bash", "bash", "-c", command, NULL);

If this is a long running command, I would like to have the option of killing it. For example, say I'm doing:

execlp("/bin/bash", "bash", "-c", "find / test", NULL);

After this, I know the PID of the child that is executing bash, but bash is forking a separate process to execute find.

$ ps aux | grep find
zmb       7802  0.0  0.1   5252  1104 pts/1    S+   11:17   0:00 bash -c find / test
zmb       7803  0.0  0.0   4656   728 pts/1    S+   11:17   0:00 find / test

I can kill the bash process (7802), but the find process (7803) still continues to execute. How can I ensure that the bash process propagates signals to it's children?

Answer 1

It will send a SIGTERM to the Process Group ID passed in parameter and to all children.

kill -- -$(ps -o pgid= $PID | grep -o [0-9]*)

Also, more answers on this post : Best way to kill all child processes

Answer 2

from man 2 kill :

If pid is less than -1, then sig is sent to every process in the process group whose ID is -pid.

That is you may kill all children, direct or indirect which weren't created its own process group.