Can kill in bash only send a signal from the current shell process to a process group? That is the impression from the posts that I have had so far.
Can kill in bash send a signal only to a single process whose process group has other process(es)?
In Linux, is a signal always sent from a process or the kernel to a process group, instead of to a single process?
I created a do nothing script (from user6915 @ 42901) in order to get a few processes running under one pgid:
[root@JBCLAMP001 ~]# ps x -o "%r %p %y %x %c"
PGID PID TTY TIME COMMAND
62102 62102 pts/8 00:00:00 bash
62102 62104 pts/8 00:00:00 cat
62102 62103 pts/8 00:00:00 bash
Then I killed 62104 (cat):
PGID PID TTY TIME COMMAND
62102 62102 pts/8 00:00:00 bash
62102 64207 pts/8 00:00:00 cat
62102 64206 pts/8 00:00:00 bash
It restarted one of the bash processes but I think that was just the bash process that cat was running in? Either way it appears the parent bash process stayed open. Am I on the right track or is this not what you're asking?
kill sends a signal only to all the processes of a job, instead of a process in a job, or I messed up my memory with something else. A job is a process group managed by a shell. So I was thinking kill sends a signal only to all the processes of a process group.
killapidor apgidwhich to me would indicate that it can in fact send signals to individual processes.