From owner-freebsd-hackers Sat Sep 29 14:17:36 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from mail.yadt.co.uk (yadt.demon.co.uk [158.152.4.134]) by hub.freebsd.org (Postfix) with SMTP id DC9A937B407 for ; Sat, 29 Sep 2001 14:17:00 -0700 (PDT) Received: (qmail 3751 invoked from network); 29 Sep 2001 21:16:58 -0000 Received: from gattaca.local.yadt.co.uk (HELO mail.gattaca.yadt.co.uk) (qmailr@10.0.0.2) by xfiles.yadt.co.uk with SMTP; 29 Sep 2001 21:16:58 -0000 Received: (qmail 59977 invoked by uid 1000); 29 Sep 2001 21:16:58 -0000 Date: Sat, 29 Sep 2001 22:16:58 +0100 From: David Taylor To: freebsd-hackers@FreeBSD.org Subject: Re: Doubt of system(3) Message-ID: <20010929221658.B57903@gattaca.yadt.co.uk> Mail-Followup-To: freebsd-hackers@FreeBSD.org References: <200109291527.f8TFRrU76727.toshi@jp.FreeBSD.org> <20010929153433.U59854@elvis.mu.org> <20010929214338.A57903@gattaca.yadt.co.uk> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-md5; protocol="application/pgp-signature"; boundary="EuxKj2iCbKjpUGkD" Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20010929214338.A57903@gattaca.yadt.co.uk>; from davidt@yadt.co.uk on Sat, Sep 29, 2001 at 21:43:38 +0100 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG --EuxKj2iCbKjpUGkD Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, 29 Sep 2001, David Taylor wrote: > On Sat, 29 Sep 2001, Alfred Perlstein wrote: > >=20 > > Why does it need to be corrected? What sort of bad behaviour > > are you seeing? You do 'a' and you see 'b' when you should > > see 'c'. > >=20 > > What's a, b and c? > >=20 >=20 > Well, hypothetically (I have no time to attempt to set something up to te= st > this), it looks to me like: >=20 > If you: >=20 > 1. Fork, and create a child (say, pid 10) > 2. Call system, which forks and creates a child (say, pid 11) > 3. Make the child (pid 10) exit now. > 3. Interrupt the call to _wait4(pid [=3D11], ...); >=20 I've now managed to reproduce this... Test program at http://www.yadt.demon.co.uk/system-bug.tar.gz I'm pretty sure that's incorrect behaviour, and I also beleive the original patch posted to this list should fix it... --=20 David Taylor davidt@yadt.co.uk --EuxKj2iCbKjpUGkD Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (FreeBSD) Comment: For info see http://www.gnupg.org iD8DBQE7tjpJfIqKXSsJ/xERAlePAJ9bWY/y+K7k+tn3goQYc+D/pcPpwgCgx3RP 7pfD9QO69643fLyHrUUDCWA= =DXpd -----END PGP SIGNATURE----- --EuxKj2iCbKjpUGkD-- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message