srp@babar.mmwb.ucsf.edu (Scott R. Presnell) (07/27/90)
Hey all - I have been experementing with sending processes SIGSTOP and SIGCONT from csh. This is under IRIX 3.2 - and assuming that I (not root) am doing the "kill"ing: When a process is started and backgrounded from csh, I can basically STOP and CONT it from that csh or any other csh connection. Fine. 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. 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? Thanks. - Scott -- Scott Presnell +1 (415) 476-9890 Pharm. Chem., S-926 Internet: srp@cgl.ucsf.edu University of California UUCP: ...ucbvax!ucsfcgl!srp San Francisco, CA. 94143-0446 Bitnet: srp@ucsfcgl.bitnet
jik@pit-manager.MIT.EDU (Jonathan I. Kamens) (07/28/90)
In article <srp.649092917@babar.mmwb.ucsf.edu>, srp@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. Jonathan Kamens USnail: MIT Project Athena 11 Ashford Terrace jik@Athena.MIT.EDU Allston, MA 02134 Office: 617-253-8495 Home: 617-782-0710