From owner-freebsd-current Mon Jun 17 09:00:53 1996 Return-Path: owner-current Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id JAA09931 for current-outgoing; Mon, 17 Jun 1996 09:00:53 -0700 (PDT) Received: from halloran-eldar.lcs.mit.edu (halloran-eldar.lcs.mit.edu [18.26.0.159]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id JAA09923 for ; Mon, 17 Jun 1996 09:00:51 -0700 (PDT) Received: by halloran-eldar.lcs.mit.edu; (5.65/1.1.8.2/19Aug95-0530PM) id AA01047; Mon, 17 Jun 1996 11:57:56 -0400 Date: Mon, 17 Jun 1996 11:57:56 -0400 From: Garrett Wollman Message-Id: <9606171557.AA01047@halloran-eldar.lcs.mit.edu> To: James Raynard Cc: bde@zeta.org.au, freebsd-current@freebsd.org, j@uriah.heep.sax.de, nate@sri.MT.net Subject: Re: ktrace [Was: 2.2-960612-SNAP resolver problems] In-Reply-To: <199606170030.AAA10445@jraynard.demon.co.uk> References: <199606160211.MAA00203@godzilla.zeta.org.au> <199606170030.AAA10445@jraynard.demon.co.uk> Sender: owner-current@freebsd.org X-Loop: FreeBSD.org Precedence: bulk < said: > Indeed. Apart from volume of output, is there any particular reason > why ktrace writes to a file which kdump reads in, as opposed to using > a pipe? Particularly as the first thing kdump does is > freopen(tracefile, "r", stdin)! 1) The ktrace(2) system call takes a filename as its argument, not a descriptor. 2) The present approach has the advantage of not disturbing the file descriptor table of the process being debugged, so that heisenbug effects are less likely to occur. -GAWollman -- Garrett A. Wollman | Shashish is simple, it's discreet, it's brief. ... wollman@lcs.mit.edu | Shashish is the bonding of hearts in spite of distance. Opinions not those of| It is a bond more powerful than absence. We like people MIT, LCS, ANA, or NSA| who like Shashish. - Claude McKenzie + Florent Vollant