Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!ucbvax!NUSVM.BITNET!GBOPOLY1
From: GBOPOLY1@NUSVM.BITNET (fclim)
Newsgroups: comp.sys.apollo
Subject: Re: go to old directory == 'back' ??
Message-ID: <8906280435.AA18692@umix.cc.umich.edu>
Date: 28 Jun 89 04:35:17 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 58
X-Unparsable-Date: Wed, 28 Jun 89 12:34:08 SST

>Date: 9 Jun 89 22:01:09 GMT
>From: danny%idacom%alberta%att.uucp@ucbvax.Berkeley.EDU  (Danny Wilson)
>Organization: IDACOM Electronics Ltd., Edmonton, Alta.
>Subject: go to old directory == 'back' ??
>Message-Id: <678@idacom.UUCP>
>
>When using the C shell, I have a handy alias that returns you to
>the directory you were just in. This involves making an alias
>for 'cd' and 'back':
>
>    alias cd   set old=$cwd; chdir !*
>    alias back set back=$old; set old=$cwd; cd $back; unset back; dirs
>

A better method (since you're using csh) is to use pushd.  This is faster
'cos it's a built-in function of csh.

         % pwd
         foo
         % pushd bar
         bar foo
         % pwd
         bar
         % pushd
         foo bar
         % pwd
         foo
         % pushd
         bar foo
         % pwd
         bar

You could pushd-ed more directories onto the stack internal to csh.  Use
"dirs" to list the stack.  Use "pushd <n>" to move the nth entry to the
top of the stack.

>I thought this would be a great function for the Aegis shell. I made
>the following shell scripts:
>(/com/sh scripts deleted)  (no square brackets on my keyboard -- fclim)
>
>However, because the variable 'old' gets set at a lower shell level it
>is undefined within program 'back'. Has anyone got a solution for
>a (seemingly) easy problem like this?

I was thinking of implementing pushd/popd/dirs for Aegis users but have
not get round to it.  I was thinking of using paste_buffers.
(This is one way of passing global info).  Has anyone done so yet?

>Danny Wilson
>IDACOM Electronics        danny@idacom.uucp
>Edmonton, Alberta        alberta!idacom!danny
>C A N A D A

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