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File::Spec(3)	       Perl Programmers	Reference Guide		 File::Spec(3)

NAME
       File::Spec - portably perform operations	on file	names

SYNOPSIS
	       use File::Spec;

	       $x=File::Spec->catfile('a', 'b',	'c');

       which returns 'a/b/c' under Unix. Or:

	       use File::Spec::Functions;

	       $x = catfile('a', 'b', 'c');

DESCRIPTION
       This module is designed to support operations commonly performed	on
       file specifications (usually called "file names", but not to be
       confused	with the contents of a file, or	Perl's file handles), such as
       concatenating several directory and file	names into a single path, or
       determining whether a path is rooted. It	is based on code directly
       taken from MakeMaker 5.17, code written by Andreas Koenig, Andy
       Dougherty, Charles Bailey, Ilya Zakharevich, Paul Schinder, and others.

       Since these functions are different for most operating systems, each
       set of OS specific routines is available	in a separate module,
       including:

	       File::Spec::Unix
	       File::Spec::Mac
	       File::Spec::OS2
	       File::Spec::Win32
	       File::Spec::VMS

       The module appropriate for the current OS is automatically loaded by
       File::Spec. Since some modules (like VMS) make use of facilities
       available only under that OS, it	may not	be possible to load all
       modules under all operating systems.

       Since File::Spec	is object oriented, subroutines	should not be called
       directly, as in:

	       File::Spec::catfile('a','b');

       but rather as class methods:

	       File::Spec->catfile('a','b');

       For simple uses,	File::Spec::Functions provides convenient functional
       forms of	these methods.

METHODS
       canonpath
	 No physical check on the filesystem, but a logical cleanup of a path.

	     $cpath = File::Spec->canonpath( $path ) ;

	 Note that this	does *not* collapse x/../y sections into y.  This is
	 by design.  If	/foo on	your system is a symlink to /bar/baz, then
	 /foo/../quux is actually /bar/quux, not /quux as a naive ../-removal
	 would give you.  If you want to do this kind of processing, you
	 probably want "Cwd"'s "realpath()" function to	actually traverse the
	 filesystem cleaning up	paths like this.

       catdir
	 Concatenate two or more directory names to form a complete path
	 ending	with a directory. But remove the trailing slash	from the
	 resulting string, because it doesn't look good, isn't necessary and
	 confuses OS/2.	Of course, if this is the root directory, don't	cut
	 off the trailing slash	:-)

	     $path = File::Spec->catdir( @directories );

       catfile
	 Concatenate one or more directory names and a filename	to form	a
	 complete path ending with a filename

	     $path = File::Spec->catfile( @directories,	$filename );

       curdir
	 Returns a string representation of the	current	directory.

	     $curdir = File::Spec->curdir();

       devnull
	 Returns a string representation of the	null device.

	     $devnull =	File::Spec->devnull();

       rootdir
	 Returns a string representation of the	root directory.

	     $rootdir =	File::Spec->rootdir();

       tmpdir
	 Returns a string representation of the	first writable directory from
	 a list	of possible temporary directories.  Returns the	current
	 directory if no writable temporary directories	are found.  The	list
	 of directories	checked	depends	on the platform; e.g. File::Spec::Unix
	 checks	$ENV{TMPDIR} (unless taint is on) and /tmp.

	     $tmpdir = File::Spec->tmpdir();

       updir
	 Returns a string representation of the	parent directory.

	     $updir = File::Spec->updir();

       no_upwards
	 Given a list of files in a directory (such as from "readdir()"),
	 strip out '.' and '..'.

	 SECURITY NOTE:	This does NOT filter paths containing '..', like
	 '../../../../etc/passwd', only	literal	matches	to '.' and '..'.

	     @paths = File::Spec->no_upwards( readdir $dirhandle );

       case_tolerant
	 Returns a true	or false value indicating, respectively, that
	 alphabetic case is not	or is significant when comparing file
	 specifications.  Cygwin and Win32 accept an optional drive argument.

	     $is_case_tolerant = File::Spec->case_tolerant();

       file_name_is_absolute
	 Takes as its argument a path, and returns true	if it is an absolute
	 path.

	     $is_absolute = File::Spec->file_name_is_absolute( $path );

	 This does not consult the local filesystem on Unix, Win32, OS/2, or
	 Mac OS	(Classic).  It does consult the	working	environment for	VMS
	 (see "file_name_is_absolute" in File::Spec::VMS).

       path
	 Takes no argument.  Returns the environment variable "PATH" (or the
	 local platform's equivalent) as a list.

	     @PATH = File::Spec->path();

       join
	 join is the same as catfile.

       splitpath
	 Splits	a path in to volume, directory,	and filename portions. On
	 systems with no concept of volume, returns '' for volume.

	     ($volume,$directories,$file) =
				File::Spec->splitpath( $path );
	     ($volume,$directories,$file) =
				File::Spec->splitpath( $path, $no_file );

	 For systems with no syntax differentiating filenames from
	 directories, assumes that the last file is a path unless $no_file is
	 true or a trailing separator or /. or /.. is present. On Unix,	this
	 means that $no_file true makes	this return ( '', $path, '' ).

	 The directory portion may or may not be returned with a trailing '/'.

	 The results can be passed to "catpath()" to get back a	path
	 equivalent to (usually	identical to) the original path.

       splitdir
	 The opposite of "catdir".

	     @dirs = File::Spec->splitdir( $directories	);

	 $directories must be only the directory portion of the	path on
	 systems that have the concept of a volume or that have	path syntax
	 that differentiates files from	directories.

	 Unlike	just splitting the directories on the separator, empty
	 directory names ('') can be returned, because these are significant
	 on some OSes.

       catpath()
	 Takes volume, directory and file portions and returns an entire path.
	 Under Unix, $volume is	ignored, and directory and file	are
	 concatenated.	A '/' is inserted if need be.  On other	OSes, $volume
	 is significant.

	     $full_path	= File::Spec->catpath( $volume,	$directory, $file );

       abs2rel
	 Takes a destination path and an optional base path returns a relative
	 path from the base path to the	destination path:

	     $rel_path = File::Spec->abs2rel( $path ) ;
	     $rel_path = File::Spec->abs2rel( $path, $base ) ;

	 If $base is not present or '',	then Cwd::cwd()	is used. If $base is
	 relative, then	it is converted	to absolute form using "rel2abs()".
	 This means that it is taken to	be relative to Cwd::cwd().

	 On systems with the concept of	volume,	if $path and $base appear to
	 be on two different volumes, we will not attempt to resolve the two
	 paths,	and we will instead simply return $path.  Note that previous
	 versions of this module ignored the volume of $base, which resulted
	 in garbage results part of the	time.

	 On systems that have a	grammar	that indicates filenames, this ignores
	 the $base filename as well. Otherwise all path	components are assumed
	 to be directories.

	 If $path is relative, it is converted to absolute form	using
	 "rel2abs()".  This means that it is taken to be relative to
	 Cwd::cwd().

	 No checks against the filesystem are made.  On	VMS, there is
	 interaction with the working environment, as logicals and macros are
	 expanded.

	 Based on code written by Shigio Yamaguchi.

       rel2abs()
	 Converts a relative path to an	absolute path.

	     $abs_path = File::Spec->rel2abs( $path ) ;
	     $abs_path = File::Spec->rel2abs( $path, $base ) ;

	 If $base is not present or '',	then Cwd::cwd()	is used. If $base is
	 relative, then	it is converted	to absolute form using "rel2abs()".
	 This means that it is taken to	be relative to Cwd::cwd().

	 On systems with the concept of	volume,	if $path and $base appear to
	 be on two different volumes, we will not attempt to resolve the two
	 paths,	and we will instead simply return $path.  Note that previous
	 versions of this module ignored the volume of $base, which resulted
	 in garbage results part of the	time.

	 On systems that have a	grammar	that indicates filenames, this ignores
	 the $base filename as well. Otherwise all path	components are assumed
	 to be directories.

	 If $path is absolute, it is cleaned up	and returned using
	 "canonpath".

	 No checks against the filesystem are made.  On	VMS, there is
	 interaction with the working environment, as logicals and macros are
	 expanded.

	 Based on code written by Shigio Yamaguchi.

       For further information,	please see File::Spec::Unix, File::Spec::Mac,
       File::Spec::OS2,	File::Spec::Win32, or File::Spec::VMS.

SEE ALSO
       File::Spec::Unix, File::Spec::Mac, File::Spec::OS2, File::Spec::Win32,
       File::Spec::VMS,	File::Spec::Functions, ExtUtils::MakeMaker

AUTHOR
       Currently maintained by Ken Williams "<KWILLIAMS@cpan.org>".

       The vast	majority of the	code was written by Kenneth Albanowski
       "<kjahds@kjahds.com>", Andy Dougherty "<doughera@lafayette.edu>",
       Andreas Koenig "<A.Koenig@franz.ww.TU-Berlin.DE>", Tim Bunce
       "<Tim.Bunce@ig.co.uk>".	VMS support by Charles Bailey
       "<bailey@newman.upenn.edu>".  OS/2 support by Ilya Zakharevich
       "<ilya@math.ohio-state.edu>".  Mac support by Paul Schinder
       "<schinder@pobox.com>", and Thomas Wegner "<wegner_thomas@yahoo.com>".
       abs2rel() and rel2abs() written by Shigio Yamaguchi
       "<shigio@tamacom.com>", modified	by Barrie Slaymaker
       "<barries@slaysys.com>".	 splitpath(), splitdir(), catpath() and
       catdir()	by Barrie Slaymaker.

COPYRIGHT
       Copyright (c) 2004-2013 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.

perl v5.26.0			  2017-04-19			 File::Spec(3)

NAME | SYNOPSIS | DESCRIPTION | METHODS | SEE ALSO | AUTHOR | COPYRIGHT

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