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Unix has a huge number of directories and no good way to navigate them. Famous cd command is too simplistic to help when you have over 10K directories in the directory tree. the right way was actually invented in DOS with the advent of NCD and Orthodox managers but Unix is lagging behind and there although both orthodox manager and NCD clones re available they are not widely used.
But usually for a particular user on a particular server there is patterns of usage of this directory tree. First of all some directories are used more often, some never at all. Another common pattern is shuttling between two or three directories, repeatedly editing, compiling, running, archiving or deleting some files. This particular pattern of usage was noticed very early and pushd/popd/dirs troika is not very effective Bill Joy attempt to simplify and speed up filesystem navigation in C shell. The idea was brilliant but unfortunately nobody tried to improve the first bad implementation and eventually it became standardized (lemmings rules ;-). But the fact that underling implementation if primitive does not mean that idea cannot be reused -- one definitely can adapt the initial (and brilliant) Bill Joe idea to modern capabilities of bash or ksh93 shells. You should also look at NCD clones
pushd is essentially an elegant generalization of cd invented by Bill Joe and first implemented in C-shell: in addition to moving to a particular directory it stores the current directory in a directory stack (with optional suppression of duplicates). Right now duplicate directories can be suppressed only in tcsh (with option set dunique.) It looks like in the current versions of bash the implementation of pushd/popd is very weak and not only does not support this option but contain some bugs that corrupt directory stack in certain circumstances. And without the suppression of duplicates the functionality of push/pop is much less usable (if at all)...
Pushd can also be used with -n argument to populate stack with the set of directories. Bash also provides an environment variable called PROMPT_COMMAND. The contents of this variable are executed as a regular Bash command just before Bash displays a prompt. This command can (and should) be used to maintain visited directories list.
Later on, popd can be used to restore to move to any of the directories in the stack. The weakness of implementation is that it always removes the directory from the stack.
Often they are aliased to single symbols, for example
alias +='pushd .'
alias _='popd'
Paradoxically the ksh idiom cd - that permit toggling between
two directories proved to be more useful for me then complex machinery of
push/popd/dirs (Entering cd -
return you to the last directory we used; entering it a second time "toggles"
us back again). The key idea is to generalize it permitting
to do cd -- or cd --- . The simplest way to implement
cd -- and
cd --- commands is by defining
aliases cd-- and
cd--- respectively (note that
there should be no space in alias names, but that's not bad -- saves you
one keystroke :-).
For example:
alias cd='pushd '
alias +='pushd'
alias _='popd'
alias cd-='popd'
alias cd--='popd -2'
alias cd---='popd -3'
alias d='dirs -v'
alias b='pushd +1'
The first step is to redefine cd as pushd so that you do not need to type additional letters and change your navigation habits:
alias cd='pushd '
If you do like to see the list of directories in the stack you can also use
The simplest way is to define aliases:pushd()
{
builtin pushd "$@" > /dev/null
}
alias cd-='popd'
alias cd--='popd -2'
alias cd---=popd -3'
One of the most productive ways of usage of pushd/popd/dirs troika is to to use it as a proxy to the directories favorite list. To do this we need better understand the capabilities of each of the commands in pushd/popd/dirs troika
dirs dirs [+N | -N] [-clvp]Display the list of currently remembered directories. Directories are added to the list with thepushdcommand; thepopdcommand removes directories from the list.
+N- Displays the Nth directory (counting from the left of the list printed by
dirswhen invoked without options), starting with zero.-N- Displays the Nth directory (counting from the right of the list printed by
dirswhen invoked without options), starting with zero.-c- Clears the directory stack by deleting all of the elements.
-l- Produces a longer listing; the default listing format uses a tilde to denote the home directory.
-p- Causes
dirsto print the directory stack with one entry per line.-v- Causes
dirsto print the directory stack with one entry per line, prefixing each entry with its index in the stack.popd popd [+N | -N] [-n]When no arguments are given,popdremoves the top directory from the stack and performs acdto the new top directory. The elements are numbered from 0 starting at the first directory listed withdirs; i.e.,popdis equivalent topopd +0.
+N- Removes the Nth directory (counting from the left of the list printed by
dirs), starting with zero.-N- Removes the Nth directory (counting from the right of the list printed by
dirs), starting with zero.-n- Suppresses the normal change of directory when removing directories from the stack, so that only the stack is manipulated.
pushd pushd [dir | +N | -N] [-n]Save the current directory on the top of the directory stack and thencdto dir. With no arguments,pushdexchanges the top two directories.
+N- Brings the Nth directory (counting from the left of the list printed by
dirs, starting with zero) to the top of the list by rotating the stack.-N- Brings the Nth directory (counting from the right of the list printed by
dirs, starting with zero) to the top of the list by rotating the stack.-n- Suppresses the normal change of directory when adding directories to the stack, so that only the stack is manipulated.
dir- Makes the current working directory be the top of the stack, and then executes the equivalent of `
cddir'.cds to dir.
DIRSTACK- An array variable (see section Arrays) containing the current contents of the directory stack. Directories appear in the stack in the order they are displayed by the
dirsbuiltin. Assigning to members of this array variable may be used to modify directories already in the stack, but thepushdandpopdbuiltins must be used to add and remove directories. Assignment to this variable will not change the current directory. IfDIRSTACKis unset, it loses its special properties, even if it is subsequently reset.
dirs command is very useful
if we try to use pushd/popd
as a favorites list. If nothing else it provides you with the list of favories:
small but useful improvement over pitiful standard bash mode ;-).
To put directory into the stack you can use the ability to use
pushd
simply store directories using option -n. Initial
population of the list of favorites can be done in the
.profile from predefined list.
After populating the DIRSTACK you can use shortcuts to directories
via cd ~1,
cd ~2, ... notation.
For example if :
dirs -v
0 ~
1 /var/log
2 /usr/local
Then
cd
~1 is equal to
cd /var/log
and
cd
~2 is equal to cd /usr/local
Notes
The first successful implementation of the idea of reusable history of visited directories as a basis for advanced navigation was implmented in Xtree. There are seleral good Xtree clones for Unix so one can try to use this concept. See for example UnixTree,
and Ytree
As they same on the webpage "Don't leave $HOME without it!"
Dr. Nikolai Bezroukov
directory stack
Long ago having aliased "pu" and "po" to pushd and popd, I've moved on to showing my current directory stack with
alias d='dirs -v'
and rolling through the stack with
alias r='pushd +1'
and single numerical values aliased to go to that directory that comes from the dir listing, eg.
alias 3='pushd +3 > /dev/null ; dirs -v'
Another single letter alias I like is "p", which I have used for displaying and setting my PATH variable, but the code is lengthy so I won't burden you with how
p - 4
p --
p ++ /some/dir
does what you want.
Roland Mainz roland.mainz at nrubsig.org
Wed Sep 12 09:32:34 PDT 2007
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Hi! ---- [Sorry for the late reply, this one was apparently rotting in my Drafts/-folder for a long time... ;-( ] Tim Bray wrote: > On Aug 8, 2007, at 10:56 AM, Richard Elling wrote: > > pushd/popd and dirs came from csh. They are invaluable when you only > > had a terminal. They are so invaluable that ksh code to implement > > them > > is on pp 244-247 of "The Kornshell Command and Programming > > Language" by > > Bolsky and Korn, ISBN 0-13-516972-0. > > Right, well, I have a 24" screen with (at this moment in time) 3 > terminals active, all of which have several directories pushed. > > I'm not religious about shells. I am *passionate* that when we > manage to get a Linux/OS-X user to try Indiana, they don't get rude > shocks in the first three minutes because some basic piece of > infrastructure that's wired into their muscle memory doesn't work. > > If I get on Solaris and !! or !prefix-of-some-previous-command or > pushd/popd doesn't work, *that's a bug*. I don't want to micromanage > how we fix it. -Tim Erm, technically the problem of "pushd/"popd" is that several shells define "pushd" and "popd" with slightly different functionality/options and there is no POSIX specification which could be used as guidance (neither is it possible to just tack-on some functions to the shell without checking whether this is allowed by the POSIX shell spec) ... ... but for interactive ksh93 sessions the solution is AFAIK quite easy: ksh93 has a feature called "FPATH" which specifies a path (similar like the "PATH" variable) from which shell functions can be loaded dynamically at runtime. For ksh93 shipped with Solaris >= 11/B72 in interactive mode this could be used to load the matching functions "pushd"/"popd"/"dirs" from /usr/demo/ksh/fun/ via adding a -- snip -- FPATH+="/usr/demo/ksh/fun/" -- snip -- to /etc/ksh.kshrc BTW: As a mid- or long-term project we'd like to add a larger shell function library at the /usr/lib/shell/ksh/ directory (see CR 6601968 ("RFE: Add /usr/lib/shell/ksh/ as a place to store loadable shell functions")) which would move "pushd"/"popd"/"dirs" out of the demo directory to something like /usr/lib/shell/ksh/org/opensolaris/dirutil/ , giving non-interactive shell scripts a permanent location they can rely on. ---- Bye, Roland
directory stack
Long ago having aliased "pu" and "po" to pushd and popd, I've moved on to showing my current directory stack with
alias d='dirs -v'
and rolling through the stack with
alias r='pushd +1'
and single numerical values aliased to go to that directory that comes from the dir listing, eg.
alias 3='pushd +3 > /dev/null ; dirs -v'
Another single letter alias I like is "p", which I have used for displaying and setting my PATH variable, but the code is lengthy so I won't burden you with how
p - 4
p --
p ++ /some/dir
does what you want.
I really like the directory bookmark/browsing ability of tcsh when aliasing the pushd command to cd. Using bash, I would naturally like to have the same abilities, but this turns out to be far from obvious to achieve.The following listing is of a tcsh session displaying the desired functionality:
$ cd dir3 $ dirs 0 ~/tmp/dir1/dir2/dir3 1 ~/tmp/dir1/dir2 2 ~/tmp/dir1 3 ~/tmp $ cd +2 $ pwd /home/user/tmp/dir1 $ dirs 0 ~/tmp/dir1 1 ~/tmp 2 ~/tmp/dir1/dir2/dir3 3 ~/tmp/dir1/dir2 $To get the above behavior a few settings needs to be put into the ~/.tcshrc initializations file:
# .tcshrc alias dirs 'dirs -vl' set dunique set pushdsilent set pushdtohome alias cd 'pushd \!*'Things gets a little complicated when trying to mimic these tcsh settings in bash, because no counterparts exists. This does, of course, not mean that it is not possible, but is does mean that scripting is necessary:
# .bashrc alias dirs='dirs -v' cd() { MAX=10 LEN=${#DIRSTACK[@]} if [ $# -eq 0 ] || [ "$1" = "-" ]; then builtin cd "$@" pushd -n $OLDPWD > /dev/null else pushd "$@" > /dev/null || return 1 fi if [ $LEN -gt 1 ]; then for i in `seq 1 $LEN`; do eval p=~$i if [ "$p" = "$PWD" ]; then popd -n +$i > /dev/null break fi done fi if [ $LEN -ge $MAX ]; then popd -n -0 > /dev/null fi }When this function is put into the ~/.bashrc initialization file, the bash cd command behave exactly as it does in tcsh.
Dave Rutherford
Fri, 15 Jul 2005 21:22:51 -0700On 7/15/05, Ben Horowitz <[EMAIL PROTECTED]> wrote: > I grew to appreciate one feature of tcsh: the ability to use > the commands pushd -v, and popd -v. > > As you know, when the bash pushd and popd commands are successful, > they print the directory stack. In tcsh, one can additionally issue > the command pushd -v, which is like the bash commands pushd followed > by dirs -v. This feature appears not to be available in bash. > > tcsh> pushd -v /tmp > 0 /tmp > 1 / Does this do the trick? pushd () { local verbose=0; if [ "$1" = "-v" ]; then verbose=1; shift; fi; builtin pushd "$@"; if [ $verbose -eq 1 ]; then for w in $@; do echo "$w ${DIRSTACK[$w]}"; done; fi } Barely tested (and with bash 3.0 at that), but it seems to do what you want. popd would be very similar, of course. Dave===Here's a first cut. Salt to taste (yes, you should use getopts): pushd() { local es case "$1" in -v) vflag=y; shift ;; esac builtin pushd "$@" es=$? [ -n "$vflag" ] && dirs -v return $es } -
I was working with linux quite a bit today, and frequently changing between directories, when I wondered if there was a way to go back to the directory I was in previously.
Turns out there is a way:
cd ~-So if I was doing something like this:[pete@bigred /]$ cd /etc [pete@bigred etc]$ cd /usr/local [pete@bigred local]$ cd ~- [pete@bigred etc]$ pwd /etcIf you want to create a command so you don't have to type~-you can create an alias:alias cdb='cd ~-'This~-thing works great if you only need to go back one directory, but what if you wanted to go back two directories. Continuing the last code sample:[pete@bigred etc]$ cd ~- [pete@bigred local]$ cd ~- [pete@bigred etc]$ pwd /etcWe are back to/etcand not/our starting point. What I want is something that keeps a history of the directories I've been to.It turns out that the Bash (the "Bourne again shell") has a directory stack builtin. Three command line tools for manipulating the stack are avaliable
dirs,pushd, andpopd. More info about the directory stack in bash here.If we
pushda directory onto the directory stack, we can retreive the top of the stack usingdirs +1. I tried setting up some aliases to get it to work the way I wanted:alias cdd='pushd' alias cdb='cd `dirs +1`'Those worked a bit, but I ran into a lot of problems, especially when in the home directory. Also when you run pushd, popd, or dirs it always prints the contents of the stack, I don't know how to suppress that. So I figured I would post it here, and see if anyone can come up with a solution, or if anyone knows of a better way of going about this.Isn't it funny how software developers will spend hours of time trying to save a few seconds of their future time.
Trackback Address: http://www.petefreitag.com/tb/66/A132A1E502B1F3B7C329191D6E9FBE4C
On 01/23/2004 at 1:19:30 AM MST John wrote:
1
cd - works. I don't think you need cd ~-.
On 04/24/2004 at 4:50:56 AM MDT Pritam wrote:
2
You can suppress the output redirecting the output to /dev/null e.g. pushd <dir-name> >> /dev/null popd >> /dev/null
On 07/11/2007 at 2:13:43 PM MDT Freddy wrote:
3
You can use small script from http://fvue.nl/cdots which defines 1-7 dots commands:
$/usr/local/share> ... sh[Tab]
$/usr/share>
Just add the following to your~/.bashrcor if you want to make this work system wide add this to/etc/bashrc:#redefine pushd and popd so they don't output the directory stack pushd() { builtin pushd "$@" > /dev/null } popd() { builtin popd "$@" > /dev/null } #alias cd so it uses the directory stack alias cd='pushd' #aliad cdb as a command that goes one directory back in the stack alias cdb'popd'The redefinition of pushd and popd redirects their output to /dev/null instead of your terminal. This prevents them from displaying the entire stack every time they are called
Re:pushd and popd (and other tricks) (Score:1)
by camh (32881) on Wednesday March 10, @06:25PM (#8526528)alias pd pushd
alias po popd
Similar to what I have, except I use pp instead of pd (because its faster to type) and pp without args takes you to your home directory (like cd without args). To go along with it, I use
alias r "pushd +1"
alias rr "cd "$OLDPWD"
If you're working within a number of directories, use pp to get to them and then use r to rotate between the directories. rr is convenient to quickly cd somewhere else to do something and then get back again.
pushd and popd (and other tricks) (Score:5, Informative)
by Komi (89040) <cgguenNO@SPAMattglobal.net> on Wednesday March 10, @02:41PM (#8524004)
(http://slashdot.org/)I've read throught the tcsh man pages and stole from other people and probably the least-known most useful trick I've found is pushd and popd (which I realias to pd and po), and of course directory stack substitution. Here's a snippet of code that's really useful: alias pd pushd
alias po popd
cd/incredi/bly/long/path/name
pd/some/other/incredi/bly/long/path/name
cp *.mp3 =1 # =1 is the first entry on the dirstack
po # returns you back to first placeThe other major time saver I use are sed and awk. I used each for a specific purpose. Sed works great for substitution, and awk I use to grab columns of data. Here's a sample of how I'd use both together. This will list the home directories of the users on a machine. It's simple, but there's a ton you can do with this technique.
who | awk '{print $1}' | sort | uniq | sed 's@^@/home/@g'
Here's other stuff I have grouped by sections in my
.cshrc First, I have my shell variables. The comments say what they do. The most important one is autolist.
set autolist # automatically lists possibilities after ambiguous completion
set dunique # removes duplicate entries in the dirstack
set fignore=(\~) # files ending in ~ will be ignored by completion
set histdup=prev # do not allow consecutive duplicate history entries
set noclobber # output redirection will not overwrite an existing file
set notify # notifies when a job completes
set symlinks=ignore # treats symbolic directories like real directories
set time=5 # processes that run longer than $time seconds will be timed.Second, bindkeys are pretty neat. I rebind the up and down arrow keys. By default they scroll up and down one at a time through the history. You can bind them to search the history based on what you've typed so far.
bindkey -k up history-search-backward # up arrow key
bindkey -k down history-search-forward # down arrow keyThird, completes allow for customizing tab completion. When I change directories, tab only completes directory names. This also works for aliases, sets, setenvs, etc.
complete cd 'p/1/d/'
complete alias 'p/1/a/'
complete setenv 'p/1/e/'
complete set 'p/1/s/'Fourth, I have all my aliases. I had to cut a bunch because of the lameness filter.
Re:pushd and popd (and other tricks) (Score:1)alias cwdcmd 'ls'
alias precmd 'echo -n "\033]0;$USER@`hostname` : $PWD\007"'
alias pd 'pushd'
alias po 'popd'
alias dirs 'dirs -v'
alias path 'printf "${PATH:as/:/\n/}\n"'
alias ff 'find . -name '\''\!:1'\'' -print \!:2*'
alias aw 'awk '\''{print $'\!:1'}'\'''
alias sub 'sed "s@"\!:1"@"\!:2"@g"'
by MasterLock (581630) on Wednesday March 10, @03:23PM (#8524465)Two of my most handy aliases (tcsh and 4DOS/4NT) are:
alias mcd 'md \!*; cd \!*'
alias rcd 'setenv OLD_DIR `pwd`;cd
..;echo $OLD_DIR;rd "$OLD_DIR"; unsetenv OLD_DIR' Usage: ~/> mcd junkDir ~/junk> -- do commands, unzip files, et cetera -- ~/junk> rcd ~/> -- back where you were and the dir is gone -- Re:pushd and popd (and other tricks) (Score:1, Informative)
by Anonymous Coward on Wednesday March 10, @03:25PM (#8524497)alias pd pushd
alias po popd
cd/incredi/bly/long/path/name
pd/some/other/incredi/bly/long/path/name
cp *.mp3 =1 # =1 is the first entry on the dirstack
po # returns you back to first place
cd/some/directory/
cd/another/directory/
cp *.mp3 ~-
cd ~-Re:pushd and popd (and other tricks) (Score:2, Informative)
by MasterLock (581630) on Wednesday March 10, @03:33PM (#8524577)f my most handy aliases (tcsh and 4DOS/4NT) are:
alias mcd 'md \!*; cd \!*'
alias rcd 'setenv OLD_DIR `pwd`; cd..; echo $OLD_DIR;rd "$OLD_DIR"; unsetenv OLD_DIR'
Usage:
~/> mcd junkDir
~/junk> -- do commands, unzip files, et cetera --
~/junk> rcd
~/> -- back where you were and the dir is gone --Microsoft Windows XP - Popd
Popd
Changes the current directory to the directory stored by the pushd command.
Syntax
popd
Parameters
/? : Displays help at the command prompt.
Remarks
•
Every time you use the pushd command, a single directory is stored for your use. However, you can store multiple directories by using the pushd command multiple times.
The directories are stored sequentially in a virtual stack. If you use the pushd command once, the directory in which you use the command is placed at the bottom of the stack. If you use the command again, the second directory is placed on top of the first one. The process repeats every time you use the pushd command.
You can use the popd command to change the current directory to the directory most recently stored by the pushd command. If you use the popd command, the directory on the top of the stack is removed from the stack as the current directory is changed to that directory. If you use the popd command again, the next directory on the stack is removed.•
When command extensions are enabled, the popd command removes any drive-letter assignations created by pushd.
Examples
You can use pushd and popd in a batch program to change the current directory from the one in which the batch program was run and then change it back. The following sample batch program shows how to do this:
@echo off rem This batch file deletes all .txt files in a specified directory pushd %1 del *.txt popd cls echo All text files deleted in the %1 directoryAn Introduction to the Z Shell - Directory Stacks
If you use csh, you may know about directory stacks. The
pushdcommand puts the current directory on the stack, and changes to a new directory; thepopdcommand pops a directory off the stack and changes to it.phoenix% cd phoenix% PROMPT='Z %~> ' Z ~> pushd /tmp /tmp ~ Z /tmp> pushd /usr/etc /usr/etc /tmp ~ Z /usr/etc> pushd /usr/bin /usr/bin /usr/etc /tmp ~ Z /usr/bin> popd /usr/etc /tmp ~ Z /usr/etc> popd /tmp ~ Z /tmp> pushd /etc /etc /tmp ~ Z /etc> popd /tmp ~zsh's directory stack commands work similarly. One difference is the way
pushdis handled if no arguments are given. As in csh, this exchanges the top two elements of the directory stack:Z /tmp> dirs /tmp ~ Z /tmp> pushd ~ /tmpunless the stack only has one entry:
Z ~> popd /tmp Z /tmp> dirs /tmp Z /tmp> pushd ~ /tmpor unless the
PUSHDTOHOMEoption is set:Z ~> setopt pushdtohome Z ~> pushd ~ ~ /tmpAs an alternative to using directory stacks in this manner, we can get something like a directory history by setting a few more options and parameters:
~> DIRSTACKSIZE=8 ~> setopt autopushd pushdminus pushdsilent pushdtohome ~> alias dh='dirs -v' ~> cd /tmp /tmp> cd /usr /usr> cd bin /usr/bin> cd ../pub /usr/pub> dh 0 /usr/pub 1 /usr/bin 2 /usr 3 /tmp 4 ~ /usr/pub> cd -3 /tmp> dh 0 /tmp 1 /usr/pub 2 /usr/bin 3 /usr 4 ~ /tmp> ls =2/df /usr/bin/df /tmp> cd -4 ~>Note that
=2expanded to the second directory in the history list, and thatcd -3recalled the third directory in the list.You may be wondering what all those options do.
AUTOPUSHDmadecdact likepushd. (alias cd=pushdis not sufficient, for various reasons.)PUSHDMINUSswapped the meaning ofcd +1andcd -1; we want them to mean the opposite of what they mean in csh, because it makes more sense in this scheme, and it's easier to type:~> dh 0 ~ 1 /tmp 2 /usr/pub 3 /usr/bin 4 /usr ~> unsetopt pushdminus ~> cd +1 /tmp> dh 0 /tmp 1 ~ 2 /usr/pub 3 /usr/bin 4 /usr /tmp> cd +2 /usr/pub>
PUSHDSILENTkeeps the shell from printing the directory stack each time we do acd, andPUSHDTOHOMEwe mentioned earlier:/usr/pub> unsetopt pushdsilent /usr/pub> cd /etc /etc /usr/pub /tmp ~ /usr/bin /usr /etc> cd ~ /etc /usr/pub /tmp ~ /usr/bin /usr ~> unsetopt pushdtohome ~> cd /etc ~ /usr/pub /tmp ~ /usr/bin /usr /etc>
DIRSTACKSIZEkeeps the directory stack from getting too large, much likeHISTSIZE:/etc> setopt pushdsilent /etc> cd / /> cd / /> cd / /> cd / /> cd / /> cd / /> cd / /> cd / /> dh 0 / 1 / 2 / 3 / 4 / 5 / 6 / 7 /Zsh offers a nice way to reference the directory stack quickly in your daily work. The description below is taken directly from the man page:A `~' followed by a number is replaced by the directory at that position in the directory stack. `~0' is equivalent to `~+', and `~1' is the top of the stack. `~+' followed by a number is replaced by the directory at that position in the directory stack. `~+0' is equivalent to `~+', and `~+1' is the top of the stack. `~-' followed by a number is replaced by the directory that many positions from the bottom of the stack. `~-0' is the bottom of the stack. The PUSHD_MINUS option exchanges the effects of `~+' and `~-' where they are followed by a number.dirs in Your Prompt: Better than $cwd
The C shell gives the absolute pathname of your current directory in
$cwd(14.13). Many people use that in their prompts. If you use the pushd and popd (14.6) commands, you may not always remember exactly what's in your directory stack (I don't, at least). Also, do you want to shorten your home directory pathname to just a tilde (~) so it takes less room in the prompt? Here's how: run the dirs command and use its output in your prompt. A simple alias for cd users looks like this:alias cd 'chdir \!* && set prompt="`dirs`% "'and the prompts look like:
/work/project %cd~ %cd bin~/bin %Here's what to put in .cshrc to make a multiline prompt (7.5) that shows the directory stack:
# PUT hostname.domain.name IN $hostname AND hostname IN $HOST: set hostname=`uname -n` setenv HOST `expr $hostname : '\([^.]*\).*'` alias setprompt 'set prompt="\\ ${USER}@${HOST} `dirs`\\ \! % "' alias cd 'chdir \!* && setprompt' alias pushd 'pushd \!* && setprompt' alias popd 'popd \!* && setprompt' setprompt # SET THE INITIAL PROMPTBecause bash can run a command each time it sets its prompt, and because it has built-in prompt operators (7.4), the bash version of all the stuff above fits on one line:
PS1='\n\u@\h $(dirs)\n\! \$ 'That makes a blank line before each prompt; if you don't want that, join the first and second lines of the setprompt alias or remove the first
\n. Let's push a couple of directories and watch the prompt:jerry@ora ~ 1 %pushd /work/src/perl/work/src/perl ~ jerry@ora /work/src/perl ~ 2 %cd ../cnewsjerry@ora /work/src/cnews ~ 3 %pushd ~/bin~/bin /work/src/cnews ~ jerry@ora ~/bin /work/src/cnews ~ 4 %
Of course, the prompt looks a little redundant there because each pushd command also shows the dirs output. A few commands later, though, having your directory stack in the prompt will be handy. If your directory stack has a lot of entries, the first line of the prompt can get wider than the screen. In that case, store the dirs output in a shell array (47.5) and edit it with a command like sed or with the built-in csh string editing (9.6).
For example, to show just the tail of each path in the dirs output, use the alias below; the C shell operator
:gtglobally edits all words, to the tail of each pathname:alias setprompt 'set dirs=(`dirs`); set prompt="\\ ${USER}@${HOST} $dirs:gt\\ \! % "'Watch the prompt. If you forget what the names in the prompt mean, just type
dirs:History of visited directories in BASH LG #109 By Petar Marinov
Deficiencies of the CD command
Do you realize how many times you type cd per day? Do you realize how many times you retype the same directory names again and again? Ever since I migrated from 4DOS/NT shell on Windows to using Bash on Unix platforms, I've missed its cd history access. In 4DOS/NT the history of the visited directories can be navigated by Ctrl+PgUp/Dn. Every time you go to a new directory by cd, its name automatically goes on top of an easily accessible history list.
In Bash, cd - switches between the last two directories. This is a function in the right direction but many times I wanted to go to the directory before the last, I dreamed of something like cd -2.
A little scripting creates some sanity in the directory navigation of Bash.
Installing the CD history function
To install the modified CD function, copy acd_func.sh to any directory in your $PATH, or even your home directory. At the end of your .bashrc add source acd_func.sh. Restart your bash session and then type cd --.
lotzmana@safe$ cd -- 0 ~Type cd -- to verify if the installation works. Above you may see the result 0 ~. This shows that you have one directory in your history.
lotzmana@safe$ cd work lotzmana@safe$ cd scripts lotzmana@safe$ pwd /home/petarma/work/scripts lotzmana@safe$ cd -- 0 ~/work/scripts 1 ~/work 2 ~ lotzmana@safe$ cd -2 lotzmana@safe$ pwd /home/petarmaThe cd command works as usual. The new feature is the history of the last 10 directories and the cd command expanded to display and access it. cd -- (or simply pressing ctrl+w) shows the history. In front of every directory name you see a number. cd -num with the number you want jumps to the corresponding directory from the history.
How CD with history works
lotzmana@safe$ nl -w2 -s' ' acd_func.sh 1 # do ". acd_func.sh" 2 # acd_func 1.0.5, 10-nov-2004 3 # petar marinov, http:/geocities.com/h2428, this is public domain 4 cd_func () 5 { 6 local x2 the_new_dir adir index 7 local -i cnt 8 if [[ $1 == "--" ]]; then 9 dirs -v 10 return 0 11 fi 12 the_new_dir=$1 13 [[ -z $1 ]] && the_new_dir=$HOME 14 if [[ ${the_new_dir:0:1} == '-' ]]; then 15 # 16 # Extract dir N from dirs 17 index=${the_new_dir:1} 18 [[ -z $index ]] && index=1 19 adir=$(dirs +$index) 20 [[ -z $adir ]] && return 1 21 the_new_dir=$adir 22 fi 23 # 24 # '~' has to be substituted by ${HOME} 25 [[ ${the_new_dir:0:1} == '~' ]] && the_new_dir="${HOME}${the_new_dir:1}" 26 # 27 # Now change to the new dir and add to the top of the stack 28 pushd "${the_new_dir}" > /dev/null 29 [[ $? -ne 0 ]] && return 1 30 the_new_dir=$(pwd) 31 # 32 # Trim down everything beyond 11th entry 33 popd -n +11 2>/dev/null 1>/dev/null 34 # 35 # Remove any other occurence of this dir, skipping the top of the stack 36 for ((cnt=1; cnt <= 10; cnt++)); do 37 x2=$(dirs +${cnt} 2>/dev/null) 38 [[ $? -ne 0 ]] && return 0 39 [[ ${x2:0:1} == '~' ]] && x2="${HOME}${x2:1}" 40 if [[ "${x2}" == "${the_new_dir}" ]]; then 41 popd -n +$cnt 2>/dev/null 1>/dev/null 42 cnt=cnt-1 43 fi 44 done 45 return 0 46 } 47 alias cd=cd_func 48 if [[ $BASH_VERSION > "2.05a" ]]; then 49 # ctrl+w shows the menu 50 bind -x "\"\C-w\":cd_func -- ;" 51 fi4-7: cd_func() is a function, variables are declared local and are automatically deleted at the end of the function
8-11: if the function is called with a parameter "--" then it dumps the current content of the directory history. It is stored in the same place pushd/popd keep names -- the directory stack. Storage is the same, access is different.
12-13: Argument $1 is transferred into $the_new_dir for some post-processing. Immediately after that, if there are no parameters we assume that user asked for his home directory.
14-22: If parameter begins with '-' then the user is attempting to access one of the names in the history list. $index gets the number of the directory, then we extract the corresponding name into $adir. For example, dirs +3 dumps directory #3 from the stack.
At this point in $the_new_dir we have either a name specified explicitly as a parameter or a name obtained from the history of previously visited directories.
23-25: If a directory name begins with '~' then this character has to be replaced by the actual home directory name.
26-30: pushd does the actual 'cd'. It also puts the name on top of the directory stack. stdout is redirected to /dev/null in order to completely imitate how 'cd' works. Notice that any output to stderr, for example a message telling that the directory specified by the user doesn't exist will show up, which is again similar to what 'cd' does. The function aborts if pushd fails. We also need the new directory name for further analysis and $the_new_dir carries it down the function.
31-33: Keeping track of more than 10 directories is unproductive. Since we have just pushed one on top of the stack, we trim off any that fall below 11 names deep.
34-44: We loop through all the names in the directory stack. Any name that matches the new current directory is eliminated. Again, we have to translate any name from the list which begins with '~' to its format of fully expanded home directory.
47: We assign cd to be cd_func().
48-51: If the bash version allows for macros to be assigned we make ctrl+w summon the history of visited directories.
This script defines a function. It must be sourced and not executed, so that cd_func() is parsed and stored in the current environment. Try env and you must see it after all environment variables.
Documentation page of the script
Visit the acd_func.sh man page.
Recommended Links
In case of broken links please try to use Google search. If you find the page please notify us about new location
Please visit Heiner Steven SHELLdorado the best shell scripting site on the Internet
- Unix for Advanced Users - Navigating effectively - How do I remember where I was last
- Microsoft Windows XP - Popd
- An Introduction to the Z Shell - Directory Stacks
- dirs in Your Prompt: Better than $cwd
- History of visited directories in BASH LG #109 By Petar Marinov
- PushPop.vim - Pushd-Popd implementation for vim command-line vim online
- Hints and Musings
- When I googled for a Korn shell pushd, the closest thing I found was an illicit copy (gone, but cached) of part of an O'Reilly book on shell programming. And that version did not support directory names containing spaces. Here's my implementation: first, stack operators, then popd and pd (pushd is too much to type :-). This code will NOT work with a Bourne shell (it needs functions, typeset, and arrays to function in the Korn shell manner); and it will not work with bash - but bash already has pushd and popd.
Reference
dirs
dirs [+N | -N] [-clpv]Display the list of currently remembered directories. Directories are added to the list with thepushdcommand; thepopdcommand removes directories from the list.
+N- Displays the Nth directory (counting from the left of the list printed by
dirswhen invoked without options), starting with zero.-N- Displays the Nth directory (counting from the right of the list printed by
dirswhen invoked without options), starting with zero.-c- Clears the directory stack by deleting all of the elements.
-l- Produces a longer listing; the default listing format uses a tilde to denote the home directory.
-p- Causes
dirsto print the directory stack with one entry per line.-v- Causes
dirsto print the directory stack with one entry per line, prefixing each entry with its index in the stack.
popd
popd [+N | -N] [-n]Remove the top entry from the directory stack, and
cdto the new top directory. When no arguments are given,popdremoves the top directory from the stack and performs acdto the new top directory. The elements are numbered from 0 starting at the first directory listed withdirs; i.e.,popdis equivalent topopd +0.
+N- Removes the Nth directory (counting from the left of the list printed by
dirs), starting with zero.-N- Removes the Nth directory (counting from the right of the list printed by
dirs), starting with zero.-n- Suppresses the normal change of directory when removing directories from the stack, so that only the stack is manipulated.
pushd
pushd [dir | +N | -N] [-n]Save the current directory on the top of the directory stack and then
cdto dir. With no arguments,pushdexchanges the top two directories.
+N- Brings the Nth directory (counting from the left of the list printed by
dirs, starting with zero) to the top of the list by rotating the stack.-N- Brings the Nth directory (counting from the right of the list printed by
dirs, starting with zero) to the top of the list by rotating the stack.-n- Suppresses the normal change of directory when adding directories to the stack, so that only the stack is manipulated.
dir- Makes the current working directory be the top of the stack, and then executes the equivalent of `
cddir'.cds to dir.
DIRSTACKAn array variable (see section Arrays) containing the current contents of the directory stack. Directories appear in the stack in the order they are displayed by the
dirsbuiltin. Assigning to members of this array variable may be used to modify directories already in the stack, but thepushdandpopdbuiltins must be used to add and remove directories. Assignment to this variable will not change the current directory. IfDIRSTACKis unset, it loses its special properties, even if it is subsequently reset.
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Last modified: August 15, 2009
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