Answer on sockets; Question on screen under SunOS 4.[01]

Geoff Clare gwc at root.co.uk
Tue Nov 20 00:54:34 AEST 1990


brnstnd at kramden.acf.nyu.edu (Dan Bernstein) writes:

> You know how orphaned processes are
>killed when they're stopped? Well, POSIX requires that this also happen
>to processes in an orphaned process group, even if the parent is around.
>This requirement is unreasonable, useless, and unnecessarily hurts lots
>of existing programs, but it's what the standard says.

Wrong, wrong, wrong.  That is not what the standard says at all.

Here is the relevant text from P1003.1-1990, 3.3.1.3:

	"A process that is a member of an orphaned process group shall
	not be allowed to stop in response to the SIGTSTP, SIGTTIN, or
	SIGTTOU signals.  In cases where delivery of one of these signals
	would stop such a process, the signal shall be discarded."

In other words, POSIX has fixed the revolting BSD behaviour Dan describes.
Instead of getting killed the process just gets an EIO error from read(),
write(), etc.
-- 
Geoff Clare <gwc at root.co.uk>  (Dumb American mailers: ...!uunet!root.co.uk!gwc)
UniSoft Limited, Hayne Street, London EC1A 9HH, England.   Tel: +44-71-315-6600



More information about the Comp.unix.questions mailing list