pushd/popd wanted (from net.wanted.sources)

[Kevin Szabo]

Ahh, time to post some cryptic aliases!  :-)

Seriously, it is a sufficiently difficult/un-obvious problem
that I think my posting is justified.  Please no flames
about CSH etc.  Thanks.

-------------------------------------------------------
Pushd and Popd are built into
some CSH.  However, many CSH don't have them.  I don't think you can
really simulate the action in Bourne shell, but these CSH
aliases will provide the necessary effect.  Note that
they depend on the existance of the $cwd shell variable.
If your shell doesn't provide the psuedo-variable $cwd you
will have to use the alias for CD as well.

			-- Kevin

P.S. These aliases are currently in use on a vax based BSD4.2 system
and a microsoft port of SysIII with 'berkeley enhancements' running
on a orcatech3000 (m68k based).

--------------- put in your .cshrc -----------------
#is this an interactive shell?

if ( $?prompt ) then
	source ~/.aliases
endif

--------------- put in your ~/.aliases file ------------------
# pushd, popd simulator
set	dir		#if dir is not set you will get errors

# pushd, popd simulator; uses my own directory stack
alias pd	'set dir=($dir "" "") dest=\!* dir[1]=$cwd;'\
		'if ( $dest == "" ) set dest=$dir[2] dir[2]="";'\
		'cd $dest;'\
		'set dir = ($cwd $dir);'\
		'echo $dir;'

alias dp   	'set dir[1]="";set dir=($dir "");cd $dir[1];echo $dir'

# alias for CD provides a $cwd (current working directory) variable
alias cd	'chdir \!*;set cwd=`/bin/pwd`;'

alias dirs	'echo $dir'

cd .		# set the $cwd variable immediately


# If you want to have a prompt that holds parts of the current directory...
alias cd	'chdir \!*;set cwd=`/bin/pwd`;\\
		set head=$cwd:h; set prompt="$USER [$head:t/$cwd:t] \! % "'

----------------------------------------------------------

If you want to see these babies in action, try setting the shell
variables 'verbose' and 'echo'.  You will get a blow by blow 
listing of the shell's gyrations.
-- 
Kevin Szabo  watmath!wateng!ksbszabo (U of Waterloo VLSI Group, Waterloo Ont.)