


Cwd(3p)          Perl Programmers Reference Guide         Cwd(3p)


NAME
       Cwd - get pathname of current working directory

SYNOPSIS
           use Cwd;
           my $dir = getcwd;

           use Cwd 'abs_path';
           my $abs_path = abs_path($file);

DESCRIPTION
       This module provides functions for determining the
       pathname of the current working directory.  It is
       recommended that getcwd (or another *cwd() function) be
       used in all code to ensure portability.

       By default, it exports the functions cwd(), getcwd(),
       fastcwd(), and fastgetcwd() (and, on Win32, getdcwd())
       into the caller's namespace.

   getcwd and friends
       Each of these functions are called without arguments and
       return the absolute path of the current working directory.

       getcwd
               my $cwd = getcwd();

           Returns the current working directory.

           Exposes the POSIX function getcwd(3) or re-implements
           it if it's not available.

       cwd
               my $cwd = cwd();

           The cwd() is the most natural form for the current
           architecture. For most systems it is identical to
           `pwd` (but without the trailing line terminator).

       fastcwd
               my $cwd = fastcwd();

           A more dangerous version of getcwd(), but potentially
           faster.

           It might conceivably chdir() you out of a directory
           that it can't chdir() you back into.  If fastcwd
           encounters a problem it will return undef but will
           probably leave you in a different directory.  For a
           measure of extra security, if everything appears to
           have worked, the fastcwd() function will check that it
           leaves you in the same directory that it started in.
           If it has changed it will "die" with the message
           "Unstable directory path, current directory changed



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Cwd(3p)          Perl Programmers Reference Guide         Cwd(3p)


           unexpectedly". That should never happen.

       fastgetcwd
             my $cwd = fastgetcwd();

           The fastgetcwd() function is provided as a synonym for
           cwd().

       getdcwd
               my $cwd = getdcwd();
               my $cwd = getdcwd('C:');

           The getdcwd() function is also provided on Win32 to
           get the current working directory on the specified
           drive, since Windows maintains a separate current
           working directory for each drive.  If no drive is
           specified then the current drive is assumed.

           This function simply calls the Microsoft C library
           _getdcwd() function.

   abs_path and friends
       These functions are exported only on request.  They each
       take a single argument and return the absolute pathname
       for it.  If no argument is given they'll use the current
       working directory.

       abs_path
             my $abs_path = abs_path($file);

           Uses the same algorithm as getcwd().  Symbolic links
           and relative-path components ("." and "..") are
           resolved to return the canonical pathname, just like
           realpath(3).

       realpath
             my $abs_path = realpath($file);

           A synonym for abs_path().

       fast_abs_path
             my $abs_path = fast_abs_path($file);

           A more dangerous, but potentially faster version of
           abs_path.

   $ENV{PWD}
       If you ask to override your chdir() built-in function,

         use Cwd qw(chdir);

       then your PWD environment variable will be kept up to
       date.  Note that it will only be kept up to date if all
       packages which use chdir import it from Cwd.



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Cwd(3p)          Perl Programmers Reference Guide         Cwd(3p)


NOTES
       o   Since the path seperators are different on some
           operating systems ('/' on Unix, ':' on MacPerl,
           etc...) we recommend you use the File::Spec modules
           wherever portability is a concern.

       o   Actually, on Mac OS, the "getcwd()", "fastgetcwd()"
           and "fastcwd()" functions  are all aliases for the
           "cwd()" function, which, on Mac OS, calls `pwd`.
           Likewise, the "abs_path()" function is an alias for
           "fast_abs_path()".

AUTHOR
       Originally by the perl5-porters.

       Maintained by Ken Williams <KWILLIAMS@cpan.org>

COPYRIGHT
       Copyright (c) 2004 by the Perl 5 Porters.  All rights
       reserved.

       This program is free software; you can redistribute it
       and/or modify it under the same terms as Perl itself.

       Portions of the C code in this library are copyright (c)
       1994 by the Regents of the University of California.  All
       rights reserved.  The license on this code is compatible
       with the licensing of the rest of the distribution -
       please see the source code in Cwd.xs for the details.

SEE ALSO
       File::chdir

























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