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#      Copyright (C) 2009 Jari Aalto
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=pod

=encoding UTF-8

=head1 NAME

wcd - Wherever Change Directory

chdir for DOS and Unix

=head1 SYNOPSIS

    wcd [options] [directory]

=head1 DESCRIPTION

=head2 Overview

Wcd is a command-line program to change directory fast. It saves time typing at the
keyboard. One needs to type only a part of a directory name and wcd will
jump to it. Wcd has a fast selection method in case of multiple matches and
allows aliasing and banning of directories. Wcd also includes a full screen
interactive directory tree browser with speed search.

Wcd was modeled after Norton Change Directory (NCD). NCD appeared first in
I<The Norton Utilities, Release 4>, for DOS in 1987, published by Peter Norton.

Wcd has been ported to different command-line shells: DOS command.com,
Windows cmd.exe and PowerShell, OS/2 cmd.exe, and Unix shells such as Bourne
(sh), Bourne Again (bash), Korn (ksh), Z (zsh), and C (csh) shell and others
running on any operating system.

Wcd supports 8 bit character sets on all systems, and has optional
support for Unicode. See section LOCALIZATION.

See section INSTALLATION how to setup wcd for personal use.

=head2 Basic use

By default (if no wildcards are used) wcd searches for a directory with a
name that begins with the typed name.

For instance this command will change to directory to the current user's
C</home/user/Desktop>:

    wcd Desk

When there are multiple matches, wcd will present the user a list of all
matches. The user can then make a selection with a few keystrokes (most of
the times only one).

=head2 Wildcards

Wcd supports following wildcards:

    *       matches any sequence of characters (zero or more)
    ?       matches any character
    [SET]   matches any character in the specified set,
    [!SET]  or [^SET] matches any character not in the specified set.

A set is composed of characters or ranges; a range looks like
I<character hyphen character> as in C<0-9> or C<A-Z>. The
C<[0-9a-zA-Z_]> is the minimal set of characters allowed in the
C<[..]> pattern construct. International characters (i.e. 8 bit characters) are
allowed if the system supports them. To suppress the special syntactic
significance of any of C<[]*?!^-\> inside or outside a C<[..]> construct and
match the character exactly, precede the character with a backslash (C<\>)
marker.

Using wildcards makes powerful searching possible. For instance this
matches any directory name that ends with "top":

    wcd *top

Match directories that have "top" anywhere in the name:

    wcd *top*

Match any directory name that begins with "a", "b" or "c":

    wcd [a-c]*

It is also possible to give a part of a directory path. Here Wcd searches
for directory that begins with "Desk" and which path matches I<*me/Desk*>.

    wcd me/Desk

It is allowed to type any kind of expression with slashes and wildcards.
E.g.:

    wcd src*/*1?/a*2

=head2 Other uses

If no wildcards are used and wcd finds a perfect match, wcd will ignore all
wild matches by default. This behaviour can be changed with the B<-w> option.

The interactive directory tree browser can be started by using option B<-g>.

    wcd -g

Wcd generates a treedata file where it searches the directory. On Unix and
Windows systems wcd does add symbolic links to the treedata file while
scanning the disk, but does not follow them. While following links wcd could
end up scanning infinite loops, or scan very large portions of a network.

Wcd can also change to directories that are not in the treedata file. E.g.:

    wcd ..

If wcd found a match but can't change to the directory it tries to remove
it from the default treedata file. Not from the extra treedata file. See
also option B<-k>.

Wcd keeps a directory stack which is stored on disk. The stack has a
default size of 10 and is cyclic. See options B<-z>, B<->, B<+> and
B<=>.

In multi-user environments option B<-u> can be used to change to
directories of other users.


On DOS and Windows systems it does not matter if you use a slash "/" or a
backslash "\" as a directory separator.

It is possible on DOS and Windows systems to change drive and directory in
one go by preceding the directory name with the drive name.

    wcd d:games



=head2 Windows UNC paths

The Windows versions (Command Prompt, PowerShell, MSYS, zsh, cygwin) support
Windows SMB LAN UNC paths without drive letter such as
C<\\servername\sharename>. Wcd for Windows Command Prompt makes use of the "pushd"
command to automatically map a UNC path to a drive letter. In Windows
PowerShell, MSYS, zsh and Cygwin UNC paths are fully supported. The
current working directory can be a UNC path.

=head2 Console resizing on Windows

Wcd supports console resizing in Windows 10 console and ConEmu (see
L<https://conemu.github.io/>) since version 6.0.3. The Windows 10 console must
not be in legacy mode (check the console's properties). The screen may not
refresh when the console Layout property "Wrap text output on resize" is
disabled. The screen can be refreshed manually by pressing the F5 key.


=head2 Interfaces

Wcd has three different interfaces to choose from a list of matches. The
interface can be chosen at compile time.

The first interface uses plain stdin/stdout. A numbered list is printed in
the terminal. The user has to choose from the list by typing a number
followed by <Enter>. This interface does not provide scroll back
functionality in case of a long list. The scroll back capability of the
terminal/console has to be used. It is very small and portable.

The second interface is built with the conio library. It provides a builtin
scroll back capability. The user is presented a list numbered with letters.
Choosing from a list can be done by pressing just one letter. This
interface is fast because it saves keystrokes. If possible the screen
will be restored after exiting. One who prefers to type numbers can use the
B<-N> option.

The third interface is built with the curses library. It is similar to the
conio interface. The curses version of wcd has also an additional 'graphical'
interface. It lets the user select a directory via a full screen
interactive directory tree browser. It has a vim(1) like navigation and search
method. It can be activated with option B<-g>.

By using the B<-o> option one can always fall back to the stdin/stdout
interface.

=head1 OPTIONS

=over 4

=item B<-a>

Add current path to the default treedata file.

Use this option to quickly add the current path to the default treedata
file. Re-scanning the complete disk can take a long time in some cases.

=item B<-aa>

Add current and all parent paths to the default treedata file.

=item B<-A PATH>

Scan directory tree from I<PATH> and append to the default treedata
file. Examples:

    wcd -A .
    wcd -A /home -A /etc
    wcd -A d: -A e: -A \\server\share

On Windows one can scan all shared directories of a Windows LAN server by
typing something like: C<wcd -A \\servername>.


See also option B<-S> and B<-s> and B<-E>.

=item B<-b>

Ban current path.

Wcd places the current path in the ban file. This means that wcd ignores
all matches of this directory and its sub directories.

The ban file can be edited with a text editor. Use of wildcards is
supported and names are matched against the absolute path.

Banned paths are not excluded from scanning the disk. To do that use option
B<-xf>.

=item B<-c, --direct-cd>

Direct CD mode. By default wcd works as follows:

    1. Try to find a match in the treedata file(s)
    2. If no match, try to open the directory you typed.

In direct CD mode wcd works in reversed order.

    1. Try to open the directory you typed.
    2. If not, try to find a match in the treedata file(s).


=item B<-d DRIVE>

Set drive for stack and go file (DOS only).

The stack file and the go-script are by default stored on drive C: if
environment variable I<HOME> is not set. Use this option if drive C: is a
read-only drive. This option must be used in front of the stack options B<->,
B<+> and B<=>.

=item B<-e>

Add current path to the extra treedata file.

Use this option to quickly add the current path to the extra treedata file.

=item B<-ee>

Add current and all parent paths to extra treedata file.

=item B<-E PATH>

Scan directory tree from I<PATH> and append to Extra treedata file. See
also options B<-A> and B<-S>.

=item B<-f FILE>

Read treedata file I<FILE>. Do not read the default treedata file.

=item B<+f FILE>

Read treedata file I<FILE> in addition to the default treedata file.

=item B<-g>

Graphical interface (only in version with curses interface).

Wcd starts a textual curses based 'graphical' interface. The user can
select a directory via a full-screen interactive directory tree browser. It has
a vim(1) like navigation and search method.

If no search string is given wcd presents the whole tree which is in the
default treedata file and the extra treedata files.

If a search string is given the match list is presented as a directory
tree.

The default tree layout is similar to the tree layout of the original NCD on
DOS. The difference in layout is that in NCD all directories of a same depth
level were vertically aligned over the whole tree. This was possible in NCD,
because the maximum width of a directory name in DOS was 12 (8.3) characters. On
modern operating systems directory names can be very long, so also the
differences in length can be large. Therefore folders with a same depth are
not vertically aligned over the whole tree in wcd, but only in sub-branches.
So there is some sideways movement when moving straight up and down from one
sub-branch to another sub-branch.

The navigation behaviour in Wcd is exactly the same as in the original NCD. For
instance if you push the Down key you go down to the next directory with the
same depth level, jumping over branches. This enables fast navigation through
the tree.

See options B<-Ta>, B<-TC>, and B<-Tc> to change the navigation behaviour.

=item B<-gd>

Dump the treedata files as a tree to stdout.

=item B<-G PATH>

Write go-script in directory I<PATH>. For instance on Unix, C<wcd -G PATH> will write
a go-script B<PATH/wcd.go>.

=item B<-GN, --no-go-script>

Do not create go-script. This option can be used in combination with the
option B<-j> if one does not want wcd to create a go-script.

=item B<-h, --help>

Show help and exit.

=item B<-i, --ignore-case>

Ignore case.
Dos and Windows versions of wcd ignore case default. Unix/Cygwin
versions regard case by default.

=item B<+i, --no-ignore-case>

Regard case. See also option B<-i>.

=item B<-I, --ignore-diacritics>

Ignore diacritics for Latin-based scripts.
Letters with diacritical marks match their base letter without diacritical
mark. The following Latin encodings are supported:
CP437, CP850, CP852, CP1250, CP1252, ISO-8859-1, ISO-8859-2, and Unicode
Latin-1, Latin Extended-A, and Latin Extended-B.
See also L<http://en.wikipedia.org/wiki/Diacritic>

=item B<+I, --no-ignore-diacritics>

Regard diacritics (default). See also option B<-I>.

=item B<-j, --just-go>

Just go mode.

In this mode wcd will not present a list when there is more than one
directory that matches the given directory. Wcd will just change to the
first option. When wcd is invoked again with the same arguments it will
change to the next option, and so on.

Wcd will print the directory to go to to stdout. So a different
installation method can be used. One could make the following function for
a POSIX compatible shell:

    wcd ()
    {
        cd "$($HOME/bin/wcd.exe -j $@)"
    }

When you are using an old shell that doesn't support "$()" command substitution
you have to use old style command substitution with back-quotes.

    wcd ()
    {
        cd "`$HOME/bin/wcd.exe -j $@`"
    }


On Windows systems, if one is running 4NT shell, one could make the
following alias:

    alias wcd `cd %@execstr[wcdwin32.exe -z 0 -j %1]`


This method eliminates the need of the go-script, so one can use option B<-GN>
in combination with B<-j>.

=item B<-k, --keep-paths>

Keep paths.

Keep paths in the treedata file when wcd can't change to them. The default
behaviour of wcd is that it tries to remove paths from the treedata when
wcd can't change to them. With this option this behavior is turned off.

=item B<-K, --color>

Use colors in graphical mode.

=item B<-l ALIAS>

Name the current path with I<ALIAS>. Wcd places the current path with alias
I<ALIAS> in the alias file. Aliases are case sensitive.

=item B<-ls>

Show the name of the alias file, and list all the aliases.

=item B<-m DIR>

Make directory and add to treedata file.

=item B<-L, --license>

Print the distribution license.

=item B<-M DIR>

Make directory and add to extra treedata file.

=item B<-n PATH>

Read relative treedata file from I<PATH>.

Do not read the default treedata file. The relative treedata file
should already have been created using the wcd B<+S> option.
I<PATH> may also point to a file directly.

An example. Suppose another system has been mounted to mount point
C</mnt/network>:

    wcd -n /mnt/network src

Wcd opens the relative treedata file in C</mnt/network/>. The file contains the paths
relative from that point.

=item B<+n PATH>

Read relative treedata file in addition to the default treedata file. See
option B<-n>.

=item B<-N, --numbers>

Use numbers instead of letters.

Wcd with a conio or curses based interface (see section Interfaces) presents
a match list by default numbered with letters. When the B<-N> option is used
the match list is numbered with numbers. Regardless of the B<-N> option one
can type a letter or numbers to make a selection from the list of matches.

=item B<-o>

Use stdin/stdout interface.

When for some kind of reason the conio or curses interface of wcd does not
work one can fall back to the stdin/stdout interface of wcd by using the
B<-o> option.

=item B<-od, --to-stdout>

Dump all matches to stdout.

=item B<-q, --quiet>

Quieter operation. Printing of the final match is suppressed.

=item B<-r DIR>

Remove directory and remove from the treedata file.

If the directory is empty, wcd will remove it, and try to remove it from
the treedata file.

=item B<-rmtree DIR>

Recursively remove directory and remove from the treedata file.

Wcd will remove the directory and all its sub directories and files, and
remove the directories from the treedata file.

=item B<-s>

(re)Scan disk from C<$HOME> directory. If I<HOME> is not defined the disk is
scanned from root directory /.

The existing default treedata file is overwritten.

The default scan directory can be overruled with environment variable
C<WCDSCAN>. See section ENVIRONMENT VARIABLES.

=item B<-S PATH>

Scan directory tree from I<PATH> and overwrite the default treedata file.
See also options B<-A>, B<-s> and B<-E>. E.g. with option B<-A> you
can create a default treedata file of your choice. Examples:

Unix:

    wcd -S /
    wcd -S /home -A /etc -A /usr

DOS/Windows:

    wcd -S c:/
    wcd -S c: -A d: -A \\server\share

With the Windows versions one can scan all shared directories of a Windows
LAN server by typing something like: C<wcd -S \\servername>.


=item B<+S PATH>

Scan disk from I<PATH> and place relative paths in a relative treedata file.
This file is used by the B<-n> and B<+n> options of wcd. E.g. C<wcd -n PATH
src>.

=item B<-t>

Do not strip tmp mount dir C</tmp_mnt> (Unix only)

Wcd strips by default C</tmp_mnt/> from the match. Directory
C</tmp_mnt> is used by the auto-mounter. This behaviour can be turned
off with the B<-t> option.

=item B<-T, --ascii-tree>

Draw tree with ASCII characters. Use this option if line drawing characters
are not displayed properly in your terminal.

=item B<-Ta, --alt-tree-nav>

Alternative way of navigation in the graphical tree.

In the default NCD style tree layout the B<-Ta> option disables
jumping to unrelated directories.

In compact tree mode the alternative mode makes navigation similar to
navigation in GUI file managers such as Windows Explorer or Linux KDE
Konqueror. Pressing Up and Down moves the selected folder one line up or
down. Pressing Left first folds the sub-folders and the next move left moves
really left.

You can switch on-the-fly between default and alternative navigation
by pressing <Shift-A>.

When alternative navigation mode is on, you will see an "A" in the lower right corner.

=item B<-TC, --center-tree>

Centered view in the graphical tree. The selected directory stays in the middle
of the screen. The centered mode can also be switched on and off with key <t>
in the graphical tree.

The standard non-centered behaviour, which minimises tree movement, is the same
as in the original NCD.

=item B<-Tc, --compact-tree>

By default the 'graphical' tree is drawn the same way as the original NCD on
DOS did it. On DOS a directory path could only be 66 characters in total. With
the deep directory structures of today the tree can become very wide. To
overcome this wcd can draw the tree in a compact way, similar to most GUI file
managers, with only one folder per line. Use option B<-Tc> or switch on-the-fly
with the <m> key.

=item B<-Td, --cjk-width>

Legacy East-Asian CJK (Chinese, Japanese, and Korean) fonts have certain
characters and line drawing symbols with a column width of 2, while the normal
Unicode width for these characters is 1 column. For instance the Chinese CP936
raster font on Windows and the Simsun font. Use this option for a correct
outlining of the graphical tree when a legacy CJK font is used.

When CJK mode is on, you will see a "C" in the lower right corner.

=item B<-u USER>

Scan treedata file of another user based on I<USER>, do not scan your own default
treedata file. See also section ENVIRONMENT VARIABLES for I<WCDUSERSHOME>.

On Unix/Cygwin the base directory
for user home directories is assumed to be C</home>. Wcd will look for
C</home/USER/.treedata.wcd> and C</home/USER/.wcd/.treedata.wcd>, in that
order, and read the first one that exists and is readable.
On DOS/Windows the base directory for user
home directories is assumed to be C<\\users>, so wcd tries to read
C<\\users\USER\treedata.wcd> and C<\\users\USER\.wcd\treedata.wcd>.

=item B<+u USER>

Read default treedata file of USER in addition to your own treedata
file.

=item B<-v, --verbose>

Display verbose messages. With this option wcd prints all filters, bans and
excludes.

=item B<-V, --version>

Print version information and exit.

=item B<-w, --wild-match-only>

Wild matching only. Treat all matches as wild matches.

=item B<-x PATH>

Exclude I<PATH> from scanning.

When this option is used wcd will exclude I<PATH> and all its subdirectories
when wcd is scanning a disk. Wildcards are supported and matched against
absolute paths. Option B<-x> can be used multiple times.

    wcd -x <path1> -x <path2> -s

Option B<-x> must be used in front of any scan option (B<-s>, B<-S>, B<+S>,
B<-A>, B<-E>).


On DOS/Windows systems one must specify the drive letter depending on if
environment variable I<HOME> or I<WCDHOME> is set. If I<HOME> or I<WCDHOME>
is set one needs to specify the drive letter. An example:

    wcd -x c:/temp -S c:

Otherwise do not specify drive letter.

    wcd -x /temp -s


=item B<-xf FILE>

Exclude all paths listed in I<FILE> from scanning.

When this option is used wcd will exclude all paths listed in I<FILE> and all
their subdirectories when wcd is scanning a disk. Wildcards are supported
and they are matched against absolute paths; one path per line. Be aware
that wcd will not ignore leading or trailing blanks on a line, because they
are legal characters in a directory name. Option B<-xf> can be used multiple
times. When one wants to exclude all banned paths from scanning one can do
the following (example for wcd on unix):

    wcd -xf ~/.ban.wcd -s

Wildcards are supported. For instance to exclude all your Subversion directories
with administrative files add a line with C<*/.svn>.

Option B<-xf> must be used in front of any scan option (B<-s>, B<-S>, B<+S>,
B<-A>, B<-E>).

=item B<-y, --assume-yes>

Assume Yes on all queries.

Wcd will not prompt the user with yes/no questions, but assumes the user
answers yes on all questions. This can be used in combination with option
B<-rmtree>. This option must be used in front of options that can lead
to yes/no questions.

=item B<-z NUMBER>

Set maximum stack size to NUMBER.

The default size of the stack is 10. Stack operation can be turned off by
setting the size to 0. This option must be used in front of any other stack
operations (B<->,B<+>,B<=>). Otherwise the size of the stack will be set
back to the default 10.

A correct command is:

    wcd -z 50 -

The new stack size will be 50, wcd will go one directory back. A wrong
command is:

    wcd - -z 50

Wcd goes one directory back, the stack gets the default size 10. The B<-z
50> is ignored.

Add this option as the first option to your wcd alias or function. E.g.
for the a POSIX compatible shell this would be:

    wcd ()
    {
	wcd.exe -z 50 "$@"
	. ${WCDHOME:-${HOME}}/bin/wcd.go
    }

=item B<-[NUMBER]>

Push dir NUMBER of times. Default is one.

Go back a directory. Command C<wcd -> goes one directory back. To go more
directories back add a number to it. E.g. command C<wcd -3>. The stack is
cyclic.

=item B<+[NUMBER]>

Pop dir NUMBER of times. Default is one.

Go forward a directory. Command C<wcd +> goes one directory forward. To go
more directories forward add a number to it. E.g. command C<wcd +2>. The
stack is cyclic.

=item B<=>

Show stack.

Use this option if you do not know anymore how many times to push or pop.
The stack is printed and you can choose a number. The current place in
the stack is marked with an asterisk C<*>.

=back

=head1 INSTALLATION

The current working directory of a Unix shell can only be
changed by the builtin cd(1) command. Therefore the program is always called
by a function or an alias. The function or alias sources a shell script
(go-script) which is generated by the wcd program. Wcd can only work after
the function or alias is defined.

Another important influence on your installation is the definition of
environment variables I<HOME> and I<WCDHOME>. See section ENVIRONMENT
VARIABLES.

=head2 Install for POSIX type shells

For a POSIX shell (ksh, bash, zsh, etc.) on Unix, Linux, Cygwin, or native MSYS
add the following function to the shell startup file (e.g. Bash uses
C<$HOME/.bashrc>):

    wcd ()
    {
        PATH/wcd.exe "$@"
        . ${WCDHOME:-${HOME}}/bin/wcd.go
    }

Replace I<PATH> with the location where the wcd executable has been
installed. Reload the shell initialization files or start new shell.

The location of the go-script C<wcd.go> differs per shell.

Wcd for DJGPP DOS bash and OS/2 bash require a different function. The go script is not
written in a directory C<bin>, and if I<WCDHOME> and I<HOME> are both not defined the
go-script is written on c:/.

DOS bash:

    wcd ()
    {
        PATH/wcdbash.exe "$@"
        . ${WCDHOME:-${HOME:-"c:"}}/wcd.go
    }

OS/2 bash:

    wcd ()
    {
        PATH/wcdos2bash.exe "$@"
        . ${WCDHOME:-${HOME:-"c:"}}/wcd.go
    }

The WinZsh version of wcd requires a bit different function. The go-script will never
be written in c:/.

    wcd ()
    {
        PATH/wcdwin32zsh.exe "$@"
        . ${WCDHOME:-${HOME}}/wcd.go
    }

See section FILES for more information.

=head2 Install for C-alike shells (csh, tcsh)

Add the following alias to the shell startup file C<$HOME/.cshrc> or
C<$HOME/.tcshrc> :

    if ( ${?WCDHOME} ) then
        alias wcd "PATH/wcd.exe \!* ; source $WCDHOME/bin/wcd.go"
    else
        alias wcd "PATH/wcd.exe \!* ; source $HOME/bin/wcd.go"
    endif

Replace I<PATH> with the location where the wcd executable has been installed.
Reload the shell initialization files or start a new shell.


=head2 Windows Command Prompt version

Unpack the zip file and add directory C<bin> to your environment
variable I<PATH>.

In Windows Command Prompt a Windows program cannot change the current work
directory, but a .bat file can. The batch script C<wcd.bat> runs the wcd program
which generates a new batch script C<wcdgo.bat>. Then C<wcd.bat> runs C<wcdgo.bat>
which actually changes the directory.

=head2 Windows VISTA and higher

In a Windows VISTA and higher Command Prompt you may have limited access to
directories. To get access to more directories you need administrator
rights. You can get a Command Prompt with administrator rights if you right
click on the Command Prompt icon and select I<Run as administrator>.

=head2 Windows PowerShell version

Add the following function to your PowerShell user profile. The location of
this profile is stored in the $profile variable. It is required that
one of the environment variables I<HOME> or I<WCDHOME> is defined.

    function wcd
    {
        PATH\wcdwin32psh.exe $args
        & $env:HOME\wcdgo.ps1
    }

Replace I<PATH> with the location where the wcd executable has been installed.
Start a new PowerShell. Wcd for PowerShell supports only the file system
provider. No other providers.

=head2 OS/2 Command Prompt version

In an OS/2 Command Prompt (cmd.exe) an OS/2-program can't change the current
work directory. That is why wcd generates a command script C<wcdgo.cmd> which
must be executed in the current shell. The script C<wcd.cmd> first executes
C<wcdos2.exe>, which creates the C<wcdgo.cmd> script. Then C<wcd.cmd> executes
the C<wcdgo.cmd> script.


=head1 LOCALIZATION

=over 4

=item B<LANG>

The primary language is selected with the environment variable I<LANG>. The
I<LANG> variable consists out of several parts. The first part is in small
letters the language code. The second one is optional and is the country code
in capital letters, preceded with an underscore. There is also an
optional third part: character encoding, preceded with a dot. A few
examples for POSIX standard type shells:

    export LANG=nl               Dutch
    export LANG=nl_NL            Dutch, The Netherlands
    export LANG=nl_BE            Dutch, Belgium
    export LANG=es_ES            Spanish, Spain
    export LANG=es_MX            Spanish, Mexico
    export LANG=en_US.iso88591   English, USA, Latin-1 encoding

For a complete list of language and country codes see the gettext(1)
manual:
L<http://www.gnu.org/software/gettext/manual/gettext.html#Language-Codes>
On Unix systems you can use to command locale(1) to get locale
specific information.

=item B<LANGUAGE>

With the I<LANGUAGE> environment variable you can specify a priority list
of languages, separated by colons. Wcd gives preference to I<LANGUAGE> over
I<LANG>. For instance, first Dutch and then German: C<LANGUAGE=nl:de>. You
have to first enable localization, by setting I<LANG> or I<LC_ALL> to a
value other than I<C>, before you can use a language priority list through
the I<LANGUAGE> variable. See also the gettext(1) manual:
L<http://www.gnu.org/software/gettext/manual/gettext.html#The-LANGUAGE-variable>

If you select a language which is not available you will get the standard
English messages.

=item B<WCDLOCALEDIR>

With the environment variable I<WCDLOCALEDIR> the I<LOCALEDIR> used during
compilation and installation of wcd can be overruled. I<LOCALEDIR> is used by
wcd with native language support to find the language files. The GNU
default value is C</usr/local/share/locale>. By typing C<wcd -V> wcd will print
the I<LOCALEDIR> that is used.

If you have installed wcd in a different directory than the default
directory you may need to set the environment variable I<WCDLOCALEDIR> to
point to the locale directory.


An example for Windows cmd:

    set WCDLOCALEDIR=c:/my_prefix/share/locale


An example for a POSIX shell:

    export WCDLOCALEDIR=$HOME/share/locale

=item B<LC_COLLATE>

When there are multiple directory matches wcd presents a sorted list. The
sorting depends on the locale settings. If the environment I<LANG> has been
set the matches are sorted like dictionaries or phone books are sorted in
that language. For instance dots and dashes are ignored, or letters e with
and without accent are equal, or upper and lower case is ignored.

The sorting gives preference to environment variable I<LC_COLLATE>
over I<LANG>. If you make I<LC_COLLATE> equal to C<C> or C<POSIX>,
locale sorting is turned off. For instance if you want Dutch language,
but not Dutch sorting, you can do something like this:

    export LANG=nl_NL
    export LC_COLLATE=C

=item B<LC_CTYPE>

With regard to character encoding Wcd will give preference to variable
I<LC_CTYPE> over I<LANG>. For instance to set character encoding to
UTF-8 the following environment setting can be done.

    export LC_CTYPE=en_US.UTF-8

=item B<LC_ALL>

All locale environment variables that start with I<LC_> are overruled by
the environment variable I<LC_ALL> if it is defined. Wcd gives preference to
I<LC_ALL> over I<LC_COLLATE> and I<LC_CTYPE>.

=back

=head2 WINDOWS CODE PAGES

There are two groups of code pages: DOS code pages (OEM) and Windows code pages
(ANSI). The default encoding for Windows, when configured with Western regional
settings, is ANSI CP1252. Windows programs, for instance notepad, use this
default system ANSI code page. The Windows console uses by default an OEM code
page (CP437 or CP850) for compatibility with DOS programs. If you use a DOS
version of wcd in a Windows console it will work, because of the DOS code page.
But the DOS version of wcd lacks support for long directory names and network
drives on Windows.

The Windows version of wcd is a native Windows program and will use the Windows
system ANSI code page. So on a Western regional Windows it will use code page
CP1252 for directory names and messages. In order to get consistent output,
independent of the active code page, all Windows versions of Wcd translate ANSI
output to Unicode output in the Command Prompt and PowerShell.

The console raster font only supports the original OEM code page installed with
Windows, so you have to change the console's font to true type Lucida
Console to make Unicode (and ANSI) letters appear correctly.

Non-Unicode versions of Wcd I<prior to version 5.2.0> use plain ANSI output.
For these older versions the code page of the console has to be made equal to
the system code page (changed to 1252) to make wcd for Windows work properly
with special characters such as accented characters or the Euro symbol.

The Windows system code page can be changed via the Control Panel regional
options. The Windows console code page is changed with the C<chcp> command.

When you type C<wcd -V>, the actual character encoding used by wcd is
shown. Type the command C<chcp> to display the active code page of the Windows
console.


=head2 UNICODE

Wcd has optional support for Unicode. To see if wcd was built with Unicode support
type C<wcd -V>. If your terminal/console and font supports it, you
should see the Euro symbol and Chinese characters (meaning:
"Chinese").

Wcd has been I<soft> converted to Unicode. In its core wcd handles all data
as a stream of bytes. Only the lines printed to screen are on the fly
converted to Unicode wide characters. Wcd fully relies on libc functions
and has no UTF-8 specific code. See also
L<http://www.cl.cam.ac.uk/~mgk25/unicode.html>

Wcd has optional support for Unicode matching with normalisation. To find
out whether Wcd has normalisation support type C<wcd -V>.
Wcd with Unicode normalization support will match Unicode names based on I<compatible>
equivalence. Without Unicode normalization support, names are matched
when they are binary equivalent.
See also L<http://en.wikipedia.org/wiki/Unicode_normalization>

=head3 UTF-8 on Unix/Linux

In order to view UTF-8 characters your console/terminal also needs to
support UTF-8. The xterm version that comes with XFree86 4.0 or higher
includes UTF-8 support. To activate it, start xterm(1) in a UTF-8
locale and use a font with iso10646-1 encoding, for instance with

    LC_CTYPE=en_GB.UTF-8 xterm -u8 -fn '-Misc-Fixed-Medium-R-SemiCondensed--13-120-75-75-C-60-ISO10646-1'

Modern distributions of GNU/Linux support UTF-8 by default. Other multi-byte
character encodings should also work, but that has not been tested.

Wcd assumes that the treedata files are encoded in the locale character
encoding. There are no Byte Order Marks written to treedata files.


=head3 UTF-16 on Windows

On Windows Unicode is supported in all versions of PowerShell, and in Windows
Command Prompt on Windows 7 (or higher). Unicode also works in Take Command
or TCC/LE made by JP Software, which can be used on older Windows versions
(XP/Vista).

On Windows all the directory names on disk are encoded in UTF-16 Unicode.
For non-Unicode Windows programs the Unicode characters are
translated to the default ANSI code page. For characters that are not part of the
regional setting this translation is not possible and non-Unicode programs
print a question mark or a wrong character instead.

Wcd with Unicode support will read the UTF-16 encoded directory names and
converts them internally to UTF-8. All treedata files are encoded in UTF-8
and not compatible with the non-Unicode version of Wcd. Wcd will create a
go-script encoded in UTF-8.

All versions of Windows PowerShell are able to run scripts encoded in UTF-8,
provided there is an UTF-8 BOM in the script.

Since Windows 7 it is possible in Windows Command Prompt to change directory
with a batch script to a directory with Unicode letters in the name. The
directory name needs to be encoded in UTF-8, and the batch script must I<not>
have a BOM. The active code page of the Command Prompt needs to be set to 65001
(UTF-8) prior to the cd command. Wcd for Command Prompt will create such a go
script C<wcdgo.bat>. It first changes the code page to 65001, then changes
directory, and finally sets the code page back to the original code page.

You need to set the font to True Type Lucida Console (not raster font) when
letters don't appear correctly.

The non-Unicode Windows version of Wcd can read Unicode treedata files since
version 5.2.0, provided there is a Byte Order Mark (BOM) in the file
(see L<http://en.wikipedia.org/wiki/Byte_order_mark>), but it can't change
to directories with Unicode letters in the name that are not part of the
default system ANSI code page. The Unicode Windows version of wcd writes
a BOM in the UTF-8 encoded treedata files since version 5.2.0, which makes
them also readable by notepad.


=head3 UTF-8 on Cygwin

Cygwin supports Unicode since version 1.7. The Cygwin layer takes care
that the Windows UTF-16 Unicode names are converted to UTF-8. So
programs, like wcd, do not need to be aware of this and can operate
using UTF-8 encoding as on Unix/Linux. Set character encoding to UTF-8
with the I<LANG> or I<LC_CTYPE> environment variable. You may need to
rescan your drives. You need to set the font to True Type Lucida
Console (not raster font) if you use the default Cygwin console.

The Cygwin version behaves exactly as the Unix version of wcd.
There is no BOM written in the treedata files, and it is assumed
they are encoded in the B<Cygwin> locale character encoding.

=head1 FILES

If the environment variable I<WCDHOME> is set wcd will use I<WCDHOME>
instead of I<HOME>. All C<*.wcd> files are text files. They can be
edited with a text editor.
The Windows Command Prompt version of wcd behaves as
the DOS version. The Cygwin version of wcd behaves as the Unix
version.

=over 4

=item B<wcd.exe>

The program. In Unix shells the program is always called by a
function or alias, because the current working directory of a Unix
shell can only be changed by the builtin cd command. See also section
INSTALLATION.

=item B<default treedata file>

This is the default treedata file where wcd searches for matches. If it is
not readable wcd will create a new one.

    DOS: \treedata.wcd or %HOME%\treedata.wcd
    Unix: $HOME/.treedata.wcd

=item B<extra treedata file>

An optional extra treedata file. If it exists and is readable wcd will try
to find matches in this file also.

    DOS: \extra.wcd or %HOME%\extra.wcd
    Unix: $HOME/.extra.wcd

=item B<ban file>

In this optional file wcd places banned paths. See option B<-b>. Wildcards are
supported.

    DOS: \ban.wcd or %HOME%\ban.wcd
    Unix: $HOME/.ban.wcd

=item B<alias file>

Optional file with wcd aliases. See option B<-l>.

    DOS: \alias.wcd or %HOME%\alias.wcd
    Unix: $HOME/.alias.wcd

=item B<stack file>

In this file wcd stores its stack. The drive letter can be changed with
the B<-d> option.

    DOS: c:\stack.wcd or %HOME%\stack.wcd
    Unix: $HOME/.stack.wcd

The name of the stack file can be changed with environment variable I<WCDSTACKFILE>.
See section ENVIRONMENT VARIABLES.

=item B<go-script>

This is the shell script which wcd.exe creates each time. It is sourced via
a function or an alias. The drive letter can be changed with the B<-d> option.
For history reasons it is placed by default in C<$HOME/bin> on Unix
systems. The directory of this file can be changed with the option B<-G>.

    DOS bash: c:/wcd.go or $HOME/wcd.go
    Windows Command Prompt: c:\wcdgo.bat or %HOME%\wcdgo.bat
    Windows PowerShell: $env:HOME\wcdgo.ps1
    WinZsh: $HOME/wcd.go
    Cygwin/MSYS: $HOME/bin/wcd.go
    OS/2 Command Prompt: c:\wcdgo.cmd or %HOME%\wcdgo.cmd
    OS/2 bash: c:/wcd.go or $HOME/wcd.go
    Unix: $HOME/bin/wcd.go

=item B<relative treedata file>

Text file with relative paths from I<DIR>. See options B<+S>, B<-n> and
B<+n>.

    DOS: PATH\rtdata.wcd
    Unix: PATH/.rtdata.wcd

=back

=head1 ENVIRONMENT VARIABLES

=over 4

=item B<HOME>

Wcd uses by default environment variable I<HOME> to determine where to store
its files. See also section FILES. This can be overruled with environment
variable I<WCDHOME>.

I<HOME> also defines where to start scanning the disk when option B<-s> is
used. This can be overruled with the environment variable I<WCDSCAN>.


For the Unix, Cygwin, Windows PowerShell, WinZsh and MSYS version
it is required that I<HOME> or I<WCDHOME> is set. For the other
versions of wcd the use of these variables is optional.

If I<HOME> is set on DOS/Windows, wcd will place all its files
(treedata.wcd, extra.wcd, alias.wcd, ban.wcd, wcd.go) in directory
I<HOME>. The behaviour of wcd is then equal to the Unix version of
wcd. Wcd will scan the disk default from I<HOME>. Drives will not be
automatically scanned by changing to them. You need to tell wcd
explicitly. E.g.:

    wcd -S c: -A d: -A e:

Matching of directories is now global over all scanned drives.


=item B<WCDHOME>

Environment variable I<WCDHOME> can be used to change the location of wcd's
files. If both I<HOME> and I<WCDHOME> are set, I<WCDHOME> will be used instead
of I<HOME>.

In wcd versions prior to 5.1.5 I<WCDHOME> also changed the default scan directory.
This has changed. Since version 5.1.5 I<WCDHOME> does not change the default scan
directory. See option B<-s>. From version 5.1.5, use environment I<WCDSCAN> to
overrule the default scan directory.

Example for DOS, Windows, OS/2 Command Prompt:

    set WCDHOME=C:\Users\erwin\wcd

An example for POSIX type shells:

    export WCDHOME="$HOME/.wcd"

An example for Csh type shells:

    setenv WCDHOME "$HOME/.wcd"

=item B<WCDSCAN>

Use environment variable I<WCDSCAN> to overrule the default scan
directory I<HOME>. Define a colon separated list (Unix) to define more
than one directory.
On DOS/Windows make the list semi-colon separated.

Examples for DOS, Windows, OS/2 Command Prompt:

    set WCDSCAN=C:\Users\erwin;D:\data

    set WCDSCAN=%HOMEDRIVE%%HOMEPATH%;\\projectdrive\projectX

An example for POSIX type shells:

    export WCDSCAN="$HOME:/projectdisk/projectX"

An example for Csh type shells:

    setenv WCDSCAN "$HOME:/projectdisk/projectX"

=item B<WCDFILTER>

Specify filters with environment variable I<WCDFILTER>. All
directories that do not match the filter(s) are ignored. A list can be
specified by separating filters by the shell path
separator. Similar as specifying the I<PATH> variable.
The case sensitivity is mandated by the Operating system.

An example for DOS, Windows, OS/2 Command Prompt:

    set WCDFILTER=projects;doc

An example for POSIX type shells:

    export WCDFILTER="projects:doc"

An example for Csh type shells:

    setenv WCDFILTER "projects:doc"

=item B<WCDBAN>

The paths specified with environment I<WCDBAN> will be banned by wcd.
See also option B<-b>. Specify a list of paths separated by shell
I<PATH> separator.

=item B<WCDEXCLUDE>

The paths specified with environment I<WCDEXCLUDE> will be excluded by
wcd. See also options B<-x> and B<-xf>. Specify a list of paths
separated by shell I<PATH> separator.


An example for DOS, Windows, OS/2 Command Prompt:

    set WCDEXCLUDE=*/windows;*/temp;*CVS

An example for POSIX type shells:

    export WCDEXCLUDE="/dev:/tmp:*CVS"

An example for Csh type shells:

    setenv WCDEXCLUDE "/dev:/tmp:*CVS"

=item B<WCDUSERSHOME>

Set the base of user's home directories.
On DOS/Windows the default value is C<\\users>.
On Unix/Cygwin the default value is C</home>.
This variable is used to scan treedata files of other users. See also
options B<-u> and B<+u>. In verbose mode wcd will print all filters,
bans and excludes. See option B<-v>.

=item B<WCDSTACKFILE>

Wcd gives preference to I<WCDSTACKFILE> over the default stack file name (see
section FILES). With this variable each shell (or used terminal emulator) can
have its private stack of used directories.

To use a unique time based YYYYMMDD-HHMMSS file for each opened
interactive shell.

    export WCDSTACKFILE=$HOME/.wcd/stack.$(date +%Y%m%d-%H%M%S)

For a stack per xterm(1), use the xterm I<WINDOWID> environment variable:

    export WCDSTACKFILE=$HOME/.wcd/stack.$WINDOWID

For GNU screen(1), to use stack per screen:

    export WCDSTACKFILE=$HOME/.wcd/stack.$WINDOW

=item B<TERMINFO>

If the environment variable I<TERMINFO> is defined, wcd with ncurses
interface checks for a local terminal definition before checking in
the standard place. This is useful if terminal definitions are not on
a standard place. Often used standard places are C</usr/lib/terminfo>
and C</usr/share/terminfo>.

=item B<PDC_RESTORE_SCREEN>

Wcd with PDCurses interface recognizes the environment variable
I<PDC_RESTORE_SCREEN>. If this environment variable is set, PDCurses
will take a copy of the contents of the screen at the time that wcd is
started; when wcd exits, the screen will be restored.
An example for Windows Command Prompt:

    set PDC_RESTORE_SCREEN=1

Windows allows only a small buffer to be saved. So it is not always
possible to restore everything. Some garbage data may be printed in
the console after wcd exits if you have set a large buffer width.


=item B<SHELL>

Printing of C<#!$SHELL> on the first line of the go-script for POSIX
type shell or C shell is needed for 8 bit characters. Some shells
otherwise think that the go-script is a binary file and will not
source it. In Cygwin Bash the variable I<SHELL> must be set in
environment using the C<export> command, otherwise wcd can't read the
variable.


=item B<BASH>

Wcd for DOS bash uses C<$BASH> instead of C<$SHELL>, because C<$SHELL>
points to the DOS command shell. One may need to define C<$BASH> with
an C<export> command, otherwise wcd can't read the variable.


=back

=head1 SEE ALSO

sh(1),
bash(1),
csh(1),
ksh(1),
zsh(1),
locale(1),
ncurses(1),

=head1 AUTHORS

Wcd was written by Erwin Waterlander <waterlan@xs4all.nl>

Project homepage:
L<http://waterlan.home.xs4all.nl/>

SourceForge:
L<http://sourceforge.net/projects/wcd/>

The manual page formatting was provided by Jari Aalto
<jari.aalto@cante.net>.

NCD was originally written by Brad Kingsbury for Peter Norton's
"Norton Utilities" around 1987. See also
L<http://www.softpanorama.org/OFM/norton_change_directory_clones.shtml>

=cut
