Path: utzoo!attcan!uunet!mcvax!botter.cs.vu.nl!ark.cs.vu.nl!maart
From: maart@cs.vu.nl (Maarten Litmaath)
Newsgroups: comp.unix.wizards
Subject: Re: Redirect Output in the Middle of a Program - Missing Feature
Keywords: system call, C interface
Message-ID: <1266@ark.cs.vu.nl>
Date: 18 May 88 01:31:49 GMT
References: <13085@brl-adm.ARPA> <3571@gryphon.CTS.COM> <2841@cvl.umd.edu> <62@denali.UUCP> <670@esl.UUCP> <606@taux01.UUCP> <1242@ark.cs.vu.nl> <1028@unmvax.unm.edu>
Reply-To: maart@cs.vu.nl (Maarten Litmaath)
Organization: VU Informatica, Amsterdam
Lines: 17

In article <1028@unmvax.unm.edu> mike@turing.UNM.EDU.UUCP (Michael I. Bushnell) writes:
\In article <1242@ark.cs.vu.nl> maart@cs.vu.nl (Maarten Litmaath) writes:
\
\>There should be some system call to indicate that some stream of a child
\>is to be reopened. The indication will probably be some kind of signal.
\>...
\
\Sigh.  This is real hard to do for the same reason fixing vhangup is
\hard.  The file descriptors are in the processes u. area, and are thus
\unavailable to the parent when it executes the system call.

What's wrong with the following: supply the process id, and the kernel
can come up with anything you want to know about the process, including
signal indication bits, file descriptors, etc., so you can change them too.
-- 
South-Africa:                         |Maarten Litmaath @ Free U Amsterdam:
           revival of the Third Reich |maart@cs.vu.nl, mcvax!botter!ark!maart