Hello.
After the following commit, stopping a user process with SIGSTOP
does not give control to the shell:
http://leaf.dragonflybsd.org/mailarchive/commits/2005-11/msg00109.html
It only happens with a program which does fork() inside it. Here's
a simple program to demonstrate this.
$ cat a.c
#include <sys/types.h>
#include <sys/wait.h>
#include <err.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
int
main(int ac __unused, char **av)
{
pid_t pid;
int rc = -1;
switch ((pid = fork())) {
case -1: /* error */
err(1, "fork");
break;
case 0: /* child */
return execvp(av[1], av + 1);
default:
wait(&rc);
break;
}
if (rc != 0)
errx(1, "child returned %d", rc);
return 0;
}
$ gcc -g -Wall a.c && ./a.out cat
(press ctrl+Z here, and it accepts no other signals until you send
SIGCONT to the child process from another screen)
`ps' command shows that the stuck processes are marked as "TL+"
(meaning that they didn't give up even after having been stopped?).
