Bug in csh? (exec v. job control)

[Chris Torek]

> > [...]  The vi wakes up from the forked process' dying and tries
> > to print something.  Vi's process group now does not match the
> > terminal's, so the system sends the process group a SIGTOUT [sic]
> > stopping it.

> I'm not sure this is a complete explanation since I don't have
> "stty tostop" set, meaning that there should be no inhibition to
> "vi" writing its output.

The first explanation was mostly correct.  Vi is not just trying to
print something, it's trying to set the terminal modes (ioctl TIOCSETN, 
actually); "stty tostop" affects programs that are attempting to write,
but the check for ioctl is more strict:  SIGTTOU will be sent if the
process group doesn't match, regardless of (tp->t_mode & TOSTOP).

(I.e., it's a bug in csh, or in the way process groups are defined, if
you prefer.)
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 4251)
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