Index for Section 3

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Cwd(3)
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() 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.

      Re-implements the getcwd(3) (or getwd(3)) functions in Perl.

      Taint-safe.

  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).

      Taint-safe.

  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 unexpectedly". That
      should never happen.

  fastgetcwd
	my $cwd = fastgetcwd();

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

  abs_path and friends

  These functions are exported only on request.	 They each take a single
  argument and return the absolute pathname for it.

  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).

      Taint-safe.

  realpath
	my $abs_path = realpath($file);

      A synonym for abs_path().

      Taint-safe.

  fast_abs_path
	my $abs_path = fast_abs_path($file);

      A more dangerous, but potentially faster version of abs_path.

      This function is Not taint-safe : you can't use it in programs that
      work under taint mode.

  $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.

NOTES
  ·   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.

  ·   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()".

SEE ALSO
  File::chdir

Index for Section 3

Alphabetical listing for C

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