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Running the following ssh command locally:

ssh user@host tail -f /etc/passwd

Results in the following 2 processes on the far end machine (note PGID & SID):

UID  PID   PPID  PGID  SID   CMD
root 22409 4763  4763  4763  sshd -f /etc/ssh/sshd_config -R
user 22411 22409 22411 22411 tail -f /etc/passwd

[download]

As expected, when I ctrl-c out of the ssh command on the originating local computer, I loose the sshd_config process at the far end, but the tail -f child process survives and looks like this:

UID  PID   PPID  PGID  SID   CMD
user 22411 1     22411 22411 tail -f /etc/passwd

[download]

I would like for the child process to die when I ctrl-c out of the ssh command. How can I do this?

Put another way, how can I get the child process (tail -f) to be in the same process group as the parent (sshd_config)?

My first thought was to use perl's setpgrp command: setpgrp(PID, PGRP) where:

PID - Child's process ID
PGRP - Parents process group

[download]

However, this seems to always fail on SunOS. Probably because of what is described in the setpgrp camel book description:

Sets the current process group for the specified PID, 0 for the current process. Will produce a fatal error if used on a machine that doesn't implement POSIX setpgid(2) or BSD setpgrp(2). If the arguments are omitted, it defaults to 0,0 . Note that the BSD 4.2 version of setpgrp does not accept any arguments, so only setpgrp(0,0) is portable. See also POSIX::setsid() .

Any help is appreciated.

Thanks!

-Craig

In reply to Unwanted SSH child survives after ssh session by cmv

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