From owner-freebsd-current Wed Mar 19 4:18:33 2003 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7220937B401 for ; Wed, 19 Mar 2003 04:18:32 -0800 (PST) Received: from gvr.gvr.org (gvr.gvr.org [212.61.40.17]) by mx1.FreeBSD.org (Postfix) with ESMTP id 08E3543F93 for ; Wed, 19 Mar 2003 04:18:31 -0800 (PST) (envelope-from guido@gvr.org) Received: by gvr.gvr.org (Postfix, from userid 657) id 17ED01A; Wed, 19 Mar 2003 13:18:29 +0100 (CET) Date: Wed, 19 Mar 2003 13:18:28 +0100 From: Guido van Rooij To: Joris Vandalon Cc: Robert Garrett , John Angelmo , current@freebsd.org Subject: Re: tcpdump delay? Message-ID: <20030319121828.GA87034@gvr.gvr.org> References: <3E784112.4000001@veidit.net> <20030319101554.GA553@sbcglobal.net> <20030319110801.GA97489@mezzanine.vandalon.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030319110801.GA97489@mezzanine.vandalon.nl> Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Wed, Mar 19, 2003 at 12:08:01PM +0100, Joris Vandalon wrote: > > -l kills buffered output, i.e. waiting for a large amount of data before > > it starts writing > > -l doesnt kill bufferd output, in contrary, it makes the output bufferd. > > -l Make stdout line buffered. Useful if you want to see the data > while capturing it. E.g., > ``tcpdump -l | tee dat'' or ``tcpdump -l > > dat & tail -f dat''. Line buffered indeed. It does not make much sense to make it completely unbuffered because the output is ine oriented. Internally tcpdump uses setvbuf(). When not called the stdio mode is fully buffered which is even worse. -Guido To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message