snoopy@doghouse.gwd.tek.com (Snoopy) (06/12/87)
In article <2245@hoptoad.uucp> gnu@hoptoad.uucp (John Gilmore) writes: >In article <1662@munnari.oz>, kre@munnari.oz (Robert Elz) writes: >> If you have job control, a suitably authorised user (ie: root) >> can pick a random process and stop it, to be continued later. > >I wish this was true. Trouble is, the parent of that process will >receive a report that it has stopped. If the parent is a csh, there is >no problem; but if the parent is init, or a Bourne shell, I have seen >it end up killing the job that I had stopped. I never ended up poking >around enough to find out why. (This on various versions of SunOS.) >-- >Copyright 1987 John Gilmore; you may redistribute only if your recipients may. I assume this is so that job controls shells can put themselves back in foreground? If init and Bourne shell are the only problems, they could be taught to do something reasonable, but any process could be a parent. But this shouldn't be a problem for most processes, since the default action is do nothing. I assume the parent isn't notified when the child receives a SIGCONT? (since it's normally the parent that sent it) Would the parent then become confused about the state of the child? (Thinking it was stopped when it had been restarted) It seems like using SIGSTOP and SIGCONT would be the preferrable method for doing 'live' backups. Snoopy tektronix!doghouse.gwd!snoopy snoopy@doghouse.gwd.tek.com