Re: Pause a process execution from external program

From: Pintu Agarwal
Date: Mon Jun 17 2019 - 08:25:41 EST

On Fri, Jun 14, 2019 at 1:13 AM Valdis KlÄtnieks
<valdis.kletnieks@xxxxxx> wrote:
> On Thu, 13 Jun 2019 13:22:12 +0530, Shyam Saini said:
> > from command line we use ctrl-z to stop execution of a foreground
> > process but you can program
> > SIGTSTP signal handler in your application code to do the same.
> Note that if you simply fail to include a signal handler for SIGSTOP and
> SIGCONT, it will Do The Right Thing. The only programs that need worry about
> SIGTSTP are ones like 'vi' that may want to do something (like restore the
> terminal state from raw to cooked mode, etc) before they stop. That's why you
> can control-z /bin/cat without it having to include a signal handler for it.
> % kill -STOP `pidof process-to-stop` # stop it
> % kill -CONT `pidof process-to-stop` # and make it run again.
> No source code modifications needed. No source needed.
> Now, if you want to make it stop at a *specific point*, then you're into
> ptrace territory, and source will be helpful.
Yes, I think ptrace can serve our purpose.
Thank you so much.