[comp.mail.elm] Ignoring Hangups

xev@hstbme.mit.edu (Xev Gittler) (06/04/88)

I know there was a whole discussion on this topic before, but I missed
it. Could someone tell me the reason that elm ignores HUP's at some
points, and mre importantly, is it bad to change it not to ignore
them?

					Xev Gittler
					xev@hstbme.mit.edu, or
					xev@athena.mit.edu

mb@ttidca.TTI.COM (Michael Bloom) (06/06/88)

In article <5615@bloom-beacon.MIT.EDU> xev@hstbme.mit.edu (Xev Gittler) writes:

> ... Could someone tell me the reason that elm ignores HUP's at some
>points, and mre importantly, is it bad to change it not to ignore
>them?

I think it may be "bad" NOT to change it, considering that on many
systems terminal opens can be invalidated (after which programs that
do ignore HUPS may subsequently loop on apparent EOF's).

While there may be critical sections to protect, it would be better to
hold the HUP rather than to ignore it.  You can do this for systems
without sighold or sigblock by using a dummy handler that just notes
that the HUP occurred and deal with it later.