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CONTENTS

NAME

File::Spec::Unix - methods used by File::Spec

SYNOPSIS

require File::Spec::Unix; # Done automatically by File::Spec

DESCRIPTION

Methods for manipulating file specifications.

METHODS

canonpath

No physical check on the filesystem, but a logical cleanup of a path. On UNIX eliminated successive slashes and successive "/.".

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

If $reduce_ricochet is present and true, then "dirname/.." constructs are eliminated from the path. Without $reduce_ricochet, if dirname is a symbolic link, then "a/dirname/../b" will often take you to someplace other than "a/b". This is sometimes desirable. If it's not, setting $reduce_ricochet causes the "dirname/.." to be removed from this path, resulting in "a/b". This may make your perl more portable and robust, unless you want to ricochet (some scripts depend on it).

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 OS2. Of course, if this is the root directory, don't cut off the trailing slash :-)

catfile

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

curdir

Returns a string representation of the current directory. "." on UNIX.

devnull

Returns a string representation of the null device. "/dev/null" on UNIX.

rootdir

Returns a string representation of the root directory. "/" on UNIX.

tmpdir

Returns a string representation of the first writable directory from the following list or "" if none are writable:

$ENV{TMPDIR}
/tmp
updir

Returns a string representation of the parent directory. ".." on UNIX.

no_upwards

Given a list of file names, strip out those that refer to a parent directory. (Does not strip symlinks, only '.', '..', and equivalents.)

file_name_is_absolute

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

path

Takes no argument, returns the environment variable PATH as an array.

join

join is the same as catfile.

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

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

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, leading empty and trailing directory entries can be returned, because these are significant on some OSs. So,

File::Spec->splitdir( "/a/b/c" );

Yields:

( '', 'a', 'b', '', 'c', '' )
catpath

Takes volume, directory and file portions and returns an entire path. Under Unix, $volume is ignored, and this is just like catfile(). On other OSs, the $volume become significant.

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( $destination ) ;
$rel_path = File::Spec->abs2rel( $destination, $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().

Based on code written by Shigio Yamaguchi.

No checks against the filesystem are made.

rel2abs

Converts a relative path to an absolute path.

$abs_path = $File::Spec->rel2abs( $destination ) ;
$abs_path = $File::Spec->rel2abs( $destination, $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 $destination 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()".

Based on code written by Shigio Yamaguchi.

No checks against the filesystem are made.

SEE ALSO

File::Spec