SIGSTOP and SIGCONT rules

[Jonathan I. Kamens]

In article <srp.649092917 at babar.mmwb.ucsf.edu>, srp at babar.mmwb.ucsf.edu
(Scott R. Presnell) writes:
|> 	If I background the process and logout of the csh that started the
|> process, then the first time I send it STOP from another csh, the
process
|> exits.

  This is not my experience on my BSD 4.3 system, which implies that
either your version of Unix does something funky with STOP AND CONT that
4.3 doesn't, or that the process to which you're sending the STOP signal
does something funky that causes it to exit if it doesn't have a tty
when it gets STOPped.  I tested this by logging into my machine via
telnet, typing "sleep 3000 &", logging out, and then STOPping and
CONTing the process from another xterm window as the same user.

|> 	What are the rules for sending SIGSTOP and SIGCONT to a process?
|> From csh?  From a daemon that nolonger has a controlling tty?  (I'm
more
|> interested in the daemon rules.)  How does the process group relate
to this?

  As far as I know (and I hope people will correct me if I'm wrong,
because I would like to hear about it), there aren't really any "rules"
for sending STOP and CONT to another process.  They are treated like any
other signals.  If this isn't true under IRIX and/or SysV, I'd sure like
to hear about it.

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