Path: utzoo!attcan!uunet!cme!libes
From: libes@cme.nist.gov (Don Libes)
Newsgroups: comp.unix.questions
Subject: Re: Some questions
Message-ID: <4919@muffin.cme.nist.gov>
Date: 2 Jul 90 20:43:55 GMT
References: <1716@jura.tcom.stc.co.uk> <1990Jun28.235729.26823@athena.mit.edu> <1990Jul1.213022.26393@athena.mit.edu>
Reply-To: libes@cme.nist.gov (Don Libes)
Organization: National Institute of Standards and Technology
Lines: 25

In article <1990Jul1.213022.26393@athena.mit.edu> jik@pit-manager.mit.edu (Jonathan I. Kamens) writes:
>  One final note about SIGCHLD signal handlers.... Don Libes has
>informed me in E-mail that SunOS 4 is one of the operating systems
>under which signal(SIGCHLD, SIG_IGN) will cause dying child processes
>to be cleaned up automatically.
>
>  The people with whom I've discussed this in the past have implied
>that this feature is a "SysV-derived" feature, but since SunOS is
>BSD-derived (or, at least, I *thought* it was), perhaps it's no longer
>safe to make that generalization.  I guess the only way to generalize
>is to say that vendors which have decided to put this feature in have
>done so, and those which haven't, haven't -- check your manual for
>more information, or write a program to test it :-).

Guy Harris has informed me that I was wrong about signal(SIGCHLD,SIG_IGN)
reaping child processes automatically on SunOS.  He is correct.

I had the unfortunate luck to be calling a subroutine that someone
else wrote which did the old wait in a loop trick, making me believe
that this long-standing behavior had been changed on my system.

Jonathon was right, originally.  SunOS 4.1 works the way that BSD
systems have worked all along.  Sorry Jonathan.

Don Libes          libes@cme.nist.gov      ...!uunet!cme-durer!libes