File::Spec - portably perform operations on file names |
File::Spec - portably perform operations on file names
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');
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 König, 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, the File::Spec::Functions manpage provides convenient functional forms of these methods.
$cpath = File::Spec->canonpath( $path ) ;
$path = File::Spec->catdir( @directories );
$path = File::Spec->catfile( @directories, $filename );
$curdir = File::Spec->curdir();
$devnull = File::Spec->devnull();
$rootdir = File::Spec->rootdir();
$tmpdir = File::Spec->tmpdir();
$updir = File::Spec->updir();
@paths = File::Spec->no_upwards( @paths );
$is_case_tolerant = File::Spec->case_tolerant();
$is_absolute = File::Spec->file_name_is_absolute( $path );
This does not consult the local filesystem on Unix, Win32, OS/2, or Mac OS (Classic). It does consult the working environment for VMS (see file_name_is_absolute in the File::Spec::VMS manpage).
@PATH = File::Spec->path();
($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.
@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 OSs.
catpath()
$full_path = File::Spec->catpath( $volume, $directory, $file );
$rel_path = File::Spec->abs2rel( $path ) ; $rel_path = File::Spec->abs2rel( $path, $base ) ;
If $base is not present or '', then 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().
On systems with the concept of a volume, this assumes that both paths are on the $destination volume, and ignores the $base volume.
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().
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()
$abs_path = File::Spec->rel2abs( $path ) ; $abs_path = File::Spec->rel2abs( $path, $base ) ;
If $base is not present or '', then 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().
On systems with the concept of a volume, this assumes that both paths are on the $base volume, and ignores the $path volume.
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 the File::Spec::Unix manpage, the File::Spec::Mac manpage, the File::Spec::OS2 manpage, the File::Spec::Win32 manpage, or the File::Spec::VMS manpage.
the File::Spec::Unix manpage, the File::Spec::Mac manpage, the File::Spec::OS2 manpage, the File::Spec::Win32 manpage, the File::Spec::VMS manpage, the File::Spec::Functions manpage, the ExtUtils::MakeMaker manpage
Kenneth Albanowski <kjahds@kjahds.com>, Andy Dougherty
<doughera@lafcol.lafayette.edu>, Andreas König
<A.Koenig@franz.ww.TU-Berlin.DE>, Tim Bunce 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.
File::Spec - portably perform operations on file names |