2 # Copyright (c) 1991, 1993
3 # The Regents of the University of California. All rights reserved.
5 # This code is derived from software contributed to Berkeley by
8 # Redistribution and use in source and binary forms, with or without
9 # modification, are permitted provided that the following conditions
11 # 1. Redistributions of source code must retain the above copyright
12 # notice, this list of conditions and the following disclaimer.
13 # 2. Redistributions in binary form must reproduce the above copyright
14 # notice, this list of conditions and the following disclaimer in the
15 # documentation and/or other materials provided with the distribution.
16 # 3. All advertising materials mentioning features or use of this software
17 # must display the following acknowledgement:
18 # This product includes software developed by the University of
19 # California, Berkeley and its contributors.
20 # 4. Neither the name of the University nor the names of its contributors
21 # may be used to endorse or promote products derived from this software
22 # without specific prior written permission.
24 # THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 # ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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31 # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 # @(#)pushd 8.2 (Berkeley) 5/4/95
38 # pushd, popd, and dirs --- written by Chris Bertin
39 # Pixel Computer Inc. ...!wjh12!pixel!pixutl!chris
40 # as modified by Patrick Elam of GTRI and Kenneth Almquist at UW
45 then if [ "$DSTACK" = "" ]
46 then echo "pushd: directory stack empty."
53 else cd $1 > /dev/null || return
55 DSTACK="$SAVE $DSTACK"
61 then echo "popd: directory stack empty."