Path: utzoo!attcan!uunet!ginosko!ctrsol!sdsu!bionet!agate!ucbvax!NUSVM.BITNET!GBOPOLY1
From: GBOPOLY1@NUSVM.BITNET (fclim)
Newsgroups: comp.sys.apollo
Subject: Re: Aliases for Aegis Commands
Message-ID: <8907290755.AA27040@umix.cc.umich.edu>
Date: 29 Jul 89 07:57:48 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 72
X-Unparsable-Date: Sat, 29 Jul 89 15:51:32 SST

Here's another alias for csh.  It implements the Korn shell feature
of cd-ing to the previous working directory :
       % pwd
       foo
       % cd bar ; pwd
       bar
       % cd - ; pwd
       foo
       % cd - ; pwd
       bar

I'm not sure if the 4.3BSD csh has this feature, but it's
certainly not available on 4.2BSD (SR9.7).  Anyway, you need to
add this to your ~/.cshrc
       set prev = ~
as well as the alias
       alias cd
           set tmp = $cwd;
           if (!* == -) cd $prev;
           if (!* != -) cd !*;
           set prev = $tmp;
           unset tmp

Please note that I have split the alias into several lines to show
the structure.  But you have to put them on a single line; it won't
work if the alias is over several lines.  It's a kludge which I
don't know how to get round  (just look at the ulgy double
comparisons of !* with -).
       alias cd 'set tmp = $cwd; if (!* == -) ... $tmp; unset tmp'

BTW, a good book to invest in is
       The Unix C Shell Field Guide
       Gail and Paul Anderson
       Prentice-Hall
       ISBN 0-13-937468-X    025
Look up the gt and gb aliases in section 6.3 on page 125-126.

Here's a interesting feature that you'll not find using /com/sh.
We all know how useful ` (back-quote) is; especially for sys_admin
personnel.
       $ wd `node_data
will put you into the /sys/node_data directory of the node you
are working on.  However, if you need to go into the node_data dir
of a different node, you have to give the full pathname starting
from the network root :
       $ wd //london/sys/node_data

This is what I did to maintain my reputation for laziness.  Firstly,
I did this (only once)
       % mkdir ~/nd ; cd ~/nd
       % foreach x (//*)
       ?    ln -s $x/sys/node_data $x:t
       ? end

Thus, I now have ~/nd/london as a link to //london/sys/node_data.
Next, I put in my ~/.cshrc
       set cdpath = (~/nd)
(See the Andersons' book on the concept of cdpath which is also
available on Bourne and Korn Shells.)

Now, I am set up for life.  No matter where I am, if I want to get
to //london/sys/node_data, I just type in
       % cd london
This feature also works with pushd :
       % pushd london
will get me to london while keeping a record of where I have been.

fclim          --- gbopoly1 % nusvm.bitnet @ cunyvm.cuny.edu
computer centre
singapore polytechnic
dover road
singapore 0513.