From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7501 invoked by alias); 3 Nov 2007 19:18:29 -0000 Received: (qmail 7491 invoked by uid 22791); 3 Nov 2007 19:18:28 -0000 X-Spam-Check-By: sourceware.org Received: from NaN.false.org (HELO nan.false.org) (208.75.86.248) by sourceware.org (qpsmtpd/0.31) with ESMTP; Sat, 03 Nov 2007 19:18:26 +0000 Received: from nan.false.org (localhost [127.0.0.1]) by nan.false.org (Postfix) with ESMTP id 2EED69834A; Sat, 3 Nov 2007 19:18:24 +0000 (GMT) Received: from caradoc.them.org (22.svnf5.xdsl.nauticom.net [209.195.183.55]) by nan.false.org (Postfix) with ESMTP id C6B049829E; Sat, 3 Nov 2007 19:18:23 +0000 (GMT) Received: from drow by caradoc.them.org with local (Exim 4.68) (envelope-from ) id 1IoOVi-0004iy-Qq; Sat, 03 Nov 2007 15:18:22 -0400 Date: Sat, 03 Nov 2007 19:18:00 -0000 From: Daniel Jacobowitz To: Eli Zaretskii Cc: gdb-patches@sourceware.org, ukleinek@informatik.uni-freiburg.de, Jim Blandy Subject: Re: [rfa] Clarify remote protocol RLE example Message-ID: <20071103191822.GA17820@caradoc.them.org> Mail-Followup-To: Eli Zaretskii , gdb-patches@sourceware.org, ukleinek@informatik.uni-freiburg.de, Jim Blandy References: <20071103161956.GA7885@caradoc.them.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.15 (2007-04-09) X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2007-11/txt/msg00032.txt.bz2 On Sat, Nov 03, 2007 at 09:01:21PM +0200, Eli Zaretskii wrote: > Response @var{data} can be run-length encoded to save space. > Run-length encoding replaces runs of identical characters with the > character @samp{*} followed by a repeat count. How about "with an initial character, the character @samp{*}, and a repeat count"? With that, I quite like your version. > > The printable > > characters @samp{$}, @samp{#}, @samp{+} and @samp{-} or with a numeric > > value greater than 126 should not be used. > > This part I simply don't understand. What does it mean ``should not > be used''? what should be done instead? break the string into several > smaller ones? May not be used (they have special syntactical meaning in the protocol). So you need to stop the RLE string one character earlier, e.g.: {0} 0 {00} 00 {000} 000 {0* } 0000 {0*!} 00000 {0*"} 000000 {0*"0} 0000000 {0*"00} 00000000 {0*%} 000000000 Rereading this, and looking at my notes in gdbserver, I don't think there is any point to the restriction on + or -. They're the protocol ack and nack characters, but they can already appear elsewhere in responses. Jim, do you see any reason they should be forbidden? -- Daniel Jacobowitz CodeSourcery