Path: csiph.com!optima2.xanadu-bbs.net!xanadu-bbs.net!news.glorb.com!usenet.stanford.edu!not-for-mail From: Chet Ramey Newsgroups: gnu.bash.bug Subject: Re: [Bug-readline] Fwd: Re: Feature proposal/request: input line highlighting Date: Fri, 21 Aug 2015 13:46:29 -0400 Lines: 53 Sender: Chet Ramey Approved: bug-bash@gnu.org Message-ID: References: <5579B2EF.5040101@computer.org> <20150612073736.GB13625@vapier> <917369538.27702.1434100972495.JavaMail.open-xchange@oxbsltgw09.schlund.de> <557AA6C9.2@computer.org> Reply-To: chet.ramey@case.edu NNTP-Posting-Host: lists.gnu.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: usenet.stanford.edu 1440182707 20489 208.118.235.17 (21 Aug 2015 18:45:07 GMT) X-Complaints-To: action@cs.stanford.edu Cc: bug-readline@gnu.org, bug-bash@gnu.org, chet@po.cwru.edu To: towo@computer.org Envelope-to: bug-bash@gnu.org In-Reply-To: Message from towo@computer.org of Fri, 12 Jun 2015 11:30:49 +0200 (id <557AA6C9.2@computer.org>) Read-Receipt-To: chet.ramey@case.edu X-Junkmail-Status: score=10/50, host=mpv6.cwru.edu X-Junkmail-Whitelist: YES (by domain whitelist at mpv2.tis.cwru.edu) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] X-Received-From: 129.22.105.37 X-BeenThere: bug-bash@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Bug reports for the GNU Bourne Again SHell List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com gnu.bash.bug:11416 > >> On 11 Jun 2015 18:10, Thomas Wolff wrote: > >> > as opposed to having a fancy colored prompt, I would like to be > >> able to > >> > set up coloring of the whole bash command input line (but not the > >> > following command output). This could be achieved by adding a variable > >> > like "AFTERPROMPT_COMMAND" which is executed after a prompt line is > >> > completed (or "PS9" which is output after a prompt line is completed). > >> > It could even be a nice idea to configure this behavior separately for > >> > bash and readline, so the users have a choice whether to color just > >> > command input, readline-handled program input, or both. > >> > I would appreciate this feature, and maybe even supply a patch if I > >> had > >> > a clue where to hook it in... > >> > >> this is already doable -- leave the end of PS1 enabling color. > >> PS1='\[\e[0;33m\]$ \[\e[34;1m\]' > >> > >> this will color the input buffer blue > thanks for your response, but that's not what I meant because the output > of the invoked programs will stay blue. I'll illustrate my idea with the > attached screenshot, showing a few possible options. So the problem is reduced to restoring the normal color before any invoked program has a chance to produce output. There are a couple of ways to do it using bash-specific functionality. Using only readline is hard because readline doesn't really have anything that just prints text to the terminal -- it's designed to manage an input buffer. This bash-specific one is easiest to describe. 1. Append the character sequence that changes the terminal to the desired color to PS1, making sure to bracket it correctly: PS1='\u@\h\$ \[\e1;34m\]' 2. Define a DEBUG trap that will restore the default terminal color settings before invoking a command: trap -- 'printf "\e[0m"' DEBUG There are ways to make this work using `bind -x' and readline's key binding to macros, but that is much more complicated. Chet -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, ITS, CWRU chet@case.edu http://cnswww.cns.cwru.edu/~chet/