Path: utzoo!utgpu!watmath!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!AUREL.CALTECH.EDU!bfox
From: bfox@AUREL.CALTECH.EDU (Brian Fox)
Newsgroups: gnu.bash.bug
Subject: Seeing control characters in aliases and functions
Message-ID: <8909151654.AA26774@aurel.caltech.edu>
Date: 15 Sep 89 16:54:45 GMT
References: <8909151157.AA01759@life.ai.mit.edu>
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Reply-To: bfox@aurel.caltech.edu
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   Date: Fri, 15 Sep 89 07:51:23 EDT
   From: James J Dempsey <jjd@alexander.bbn.com>

   >> From: Rich Salz <rsalz@BBN.COM>
   >> Subject: Re: Seeing control characters in aliases and functions
   >> To: bug-bash@prep.ai.mit.edu
   >> 
   >> In <8909142124.AA25167@aurel.caltech.edu> bfox@aurel.caltech.edu suggests
   >> I fix my "pwd" function to use "echo -e":
   >>  	function pwd () {
   >>  	  echo -n -e "\033]lBASH@${host}(${TTY}):$PWD\033\010"
   >>          }
   >> Hand smacks head, and voice goes "duh."
   >> 
   >> >Thanks for the neat function!
   >> No prob.  Of course, it makes the most sense when used with this:
   >> 	function cd() {
   >> 	    builtin cd $*;
   >> 	    pwd
   >> 	}
   >> and similar functions for pushd/popd.

   I assume the esc seqence in your alias is to update the title bar in
   your xterm window.

   I have had something similar to this for a while, but I find that it
   isn't enought to make aliases for cd, pushd and popd.  In fact, I seem
   to remember that tcsh had an automatic alias (similar to PROMPT_COMMAND)
   which would automatically get executed whenever a directory was
   changed (by cd, pushd, or popd or whatever).  This still wasn't good
   enough.  Consider the case:

   % ( cd foo/bar/baz; make )

   Your cd alias will get executed, your xterm title will change to
   reflect the new directory but it will never get set back to the
   current directory when the subshell exits.  I find that the only way
   to have an alias keep the current directory up to date in the window
   title is to use PROMPT_COMMAND.  Since the alias you use in
   PROMPT_COMMAND only uses builtins, it doesn't have that much overhead.

Huh?  Upon seeing Rich's `pwd' function, I immediately called it xtitle,
and then set PROMPT_COMMAND=xtitle.  Now everything works the way I want
it to.  No?

Brian