Cwd(3)

NAME
     getcwd - get pathname of current working directory

SYNOPSIS
         use Cwd;
         $dir = cwd;

         use Cwd;
         $dir = getcwd;

         use Cwd;
         $dir = fastgetcwd;

         use Cwd 'chdir';
         chdir "/tmp";
         print $ENV{'PWD'};

         use Cwd 'abs_path';
         print abs_path($ENV{'PWD'});

         use Cwd 'fast_abs_path';
         print fast_abs_path($ENV{'PWD'});


DESCRIPTION
     The getcwd() function re-implements the getcwd(3) (or getwd(3)) functions
     in Perl.

     The abs_path() function takes a single argument and returns the absolute
     pathname for that argument. It uses the same algoritm as getcwd().
     (actually getcwd() is abs_path("."))

     The fastcwd() function looks the same as getcwd(), but runs faster.  It's
     also more dangerous because 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
     unexpectedly". That should never happen.

     The fast_abs_path() function looks the same as abs_path(), but runs
     faster.  And like fastcwd() is more dangerous.

     The cwd() function looks the same as getcwd and fastgetcwd but is
     implemented using the most natural and safe form for the current
     architecture. For most systems it is identical to `pwd` (but without the
     trailing line terminator).
     It is recommended that cwd (or another *cwd() function) is used in all
     code to ensure portability.

     If you ask to override your chdir() built-in function, then your PWD
     environment variable will be kept up to date.  (See the section on
     Overriding Builtin Functions in the perlsub manpage.) Note that it will
     only be kept up to date if all packages which use chdir import it from
     Cwd.