package Cwd;
require 5.000;
require Exporter;
-use Config;
+require Config;
+
+# Use osname for portability switches (doubled to cheaply avoid -w warning)
+my $osname = $Config::Config{'osname'} || $Config::Config{'osname'};
+
=head1 NAME
=head1 SYNOPSIS
- require Cwd;
- $dir = Cwd::getcwd();
+ use Cwd;
+ $dir = cwd;
+
+ use Cwd;
+ $dir = getcwd;
use Cwd;
- $dir = getcwd();
+ $dir = fastgetcwd;
use Cwd 'chdir';
chdir "/tmp";
=head1 DESCRIPTION
The getcwd() function re-implements the getcwd(3) (or getwd(3)) functions
-in Perl. If you ask to override your chdir() built-in function, then your
-PWD environment variable will be kept up to date. (See
-L<perlsub/Overriding builtin functions>.)
+in Perl.
-The fastgetcwd() function looks the same as getcwd(), but runs faster.
+The fastcwd() function looks the same as getcwd(), but runs faster.
It's also more dangerous because you might conceivably chdir() out of a
directory that you can't chdir() back into.
+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 I<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
+L<perlsub/Overriding builtin functions>.) Note that it will only be
+kept up to date it all packages which use chdir import it from Cwd.
+
=cut
@ISA = qw(Exporter);
-@EXPORT = qw(getcwd fastcwd);
+@EXPORT = qw(cwd getcwd fastcwd);
@EXPORT_OK = qw(chdir);
+# use strict;
+
+sub _backtick_pwd { # The 'natural and safe form' for UNIX (pwd may be setuid root)
+ my $cwd;
+ chop($cwd = `pwd`);
+ $cwd;
+}
+
+# Since some ports may predefine cwd internally (e.g., NT)
+# we take care not to override an existing definition for cwd().
+
+*cwd = \&_backtick_pwd unless defined &cwd;
-# VMS: $ENV{'DEFAULT'} points to default directory at all times
-# 08-Dec-1994 Charles Bailey bailey@genetics.upenn.edu
-# Note: Use of Cwd::getcwd() or Cwd::chdir() (but not Cwd::fastcwd())
-# causes the logical name PWD to be defined in the process
-# logical name table as the default device and directory
-# seen by Perl. This may not be the same as the default device
-# and directory seen by DCL after Perl exits, since the effects
-# the CRTL chdir() function persist only until Perl exits.
# By Brandon S. Allbery
#
sub getcwd
{
- if($Config{'osname'} eq 'VMS') { return $ENV{'PWD'} = $ENV{'DEFAULT'} }
-
my($dotdots, $cwd, @pst, @cst, $dir, @tst);
unless (@cst = stat('.'))
unless (@tst = lstat("$dotdots/$dir"))
{
warn "lstat($dotdots/$dir): $!";
- closedir(PARENT);
- return '';
+ # Just because you can't lstat this directory
+ # doesn't mean you'll never find the right one.
+ # closedir(PARENT);
+ # return '';
}
}
while ($dir eq '.' || $dir eq '..' || $tst[0] != $pst[0] ||
# you might chdir out of a directory that you can't chdir back into.
sub fastcwd {
- if($Config{'osname'} eq 'VMS') { return $ENV{'DEFAULT'} }
-
my($odev, $oino, $cdev, $cino, $tdev, $tino);
my(@path, $path);
local(*DIR);
}
-# keeps track of current working directory in PWD environment var
-#
-# $RCSfile: pwd.pl,v $$Revision: 4.1 $$Date: 92/08/07 18:24:11 $
-#
-# $Log: pwd.pl,v $
-#
+# Keeps track of current working directory in PWD environment var
# Usage:
# use Cwd 'chdir';
# chdir $newdir;
-$chdir_init = 0;
+my $chdir_init = 0;
-sub chdir_init{
- if ($ENV{'PWD'}) {
+sub chdir_init {
+ if ($ENV{'PWD'} and $osname ne 'os2') {
my($dd,$di) = stat('.');
my($pd,$pi) = stat($ENV{'PWD'});
if (!defined $dd or !defined $pd or $di != $pi or $dd != $pd) {
- chop($ENV{'PWD'} = `pwd`);
+ $ENV{'PWD'} = cwd();
}
}
else {
- chop($ENV{'PWD'} = `pwd`);
+ $ENV{'PWD'} = cwd();
}
+ # Strip an automounter prefix (where /tmp_mnt/foo/bar == /foo/bar)
if ($ENV{'PWD'} =~ m|(/[^/]+(/[^/]+/[^/]+))(.*)|) {
my($pd,$pi) = stat($2);
my($dd,$di) = stat($1);
}
sub chdir {
- my($newdir) = shift;
- $newdir =~ s|/{2,}|/|g;
+ my $newdir = shift || ''; # allow for no arg (chdir to HOME dir)
+ $newdir =~ s|///*|/|g;
chdir_init() unless $chdir_init;
- return 0 unless (CORE::chdir $newdir);
- if ($Config{'osname'} eq 'VMS') { return $ENV{PWD} = $ENV{DEFAULT} }
+ return 0 unless CORE::chdir $newdir;
+ if ($osname eq 'VMS') { return $ENV{'PWD'} = $ENV{'DEFAULT'} }
if ($newdir =~ m#^/#) {
$ENV{'PWD'} = $newdir;
- }else{
- my(@curdir) = split(m#/#,$ENV{'PWD'});
- @curdir = '' unless @curdir;
+ } else {
+ my @curdir = split(m#/#,$ENV{'PWD'});
+ @curdir = ('') unless @curdir;
+ my $component;
foreach $component (split(m#/#, $newdir)) {
next if $component eq '.';
pop(@curdir),next if $component eq '..';
}
$ENV{'PWD'} = join('/',@curdir) || '/';
}
+ 1;
+}
+
+
+# --- PORTING SECTION ---
+
+# VMS: $ENV{'DEFAULT'} points to default directory at all times
+# 08-Dec-1994 Charles Bailey bailey@genetics.upenn.edu
+# Note: Use of Cwd::getcwd() or Cwd::chdir() (but not Cwd::fastcwd())
+# causes the logical name PWD to be defined in the process
+# logical name table as the default device and directory
+# seen by Perl. This may not be the same as the default device
+# and directory seen by DCL after Perl exits, since the effects
+# the CRTL chdir() function persist only until Perl exits.
+# This does not apply to other systems (where only chdir() sets PWD).
+
+sub _vms_cwd {
+ return $ENV{'DEFAULT'}
+}
+sub _vms_pwd {
+ return $ENV{'PWD'} = $ENV{'DEFAULT'}
+}
+sub _os2_cwd {
+ $ENV{'PWD'} = `cmd /c cd`;
+ chop $ENV{'PWD'};
+ $ENV{'PWD'} =~ s:\\:/:g ;
+ return $ENV{'PWD'};
+}
+
+if ($osname eq 'VMS') {
+
+ *cwd = \&_vms_pwd;
+ *getcwd = \&_vms_pwd;
+ *fastgetcwd = \&_vms_cwd;
+}
+elsif ($osname eq 'NT') {
+
+ *getcwd = \&cwd;
+ *fastgetcwd = \&cwd;
+}
+elsif ($osname eq 'os2') {
+ *cwd = \&_os2_cwd;
+ *getcwd = \&_os2_cwd;
+ *fastgetcwd = \&_os2_cwd;
+ *fastcwd = \&_os2_cwd;
}
+# package main; eval join('',<DATA>) || die $@; # quick test
+
1;
+__END__
+BEGIN { import Cwd qw(:DEFAULT chdir); }
+print join("\n", cwd, getcwd, fastcwd, "");
+chdir('..');
+print join("\n", cwd, getcwd, fastcwd, "");
+print "$ENV{PWD}\n";