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Updated: Wednesday, July 27, 2022
 
 

File::Spec::Unix (3)

Name

File::Spec::Unix - File::Spec for Unix, base for other File::Spec modules

Synopsis

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

Description

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



NAME
       File::Spec::Unix - File::Spec for Unix, base for other File::Spec
       modules

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

DESCRIPTION
       Methods for manipulating file specifications.  Other File::Spec
       modules, such as File::Spec::Mac, inherit from File::Spec::Unix and
       override specific methods.

METHODS
       canonpath()
         No physical check on the filesystem, but a logical cleanup of a path.
         On UNIX eliminates successive slashes and successive "/.".

             $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 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 the current directory if none from the list are
         writable:

             $ENV{TMPDIR}
             /tmp

         If running under taint mode, and if $ENV{TMPDIR} is tainted, it is
         not used.

       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.)

       case_tolerant
         Returns a true or false value indicating, respectively, that
         alphabetic is not or is significant when comparing file
         specifications.

       file_name_is_absolute
         Takes as argument a path and returns true if it is an 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 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 into volume, directory, and filename portions. On
         systems with no concept of volume, returns '' 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, empty
         directory names ('') can be returned, because these are significant
         on some OSs.

         On Unix,

             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 directory and file are
         concatenated.  A '/' is inserted if needed (though if the directory
         portion doesn't start with '/' it is not added).  On other OSs,
         $volume is 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( $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 that have a grammar that indicates filenames, this ignores
         the $base filename. 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, so the result may not be
         correct if $base contains symbolic links.  (Apply Cwd::abs_path()
         beforehand if that is a concern.)  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() 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 that have a grammar that indicates filenames, this ignores
         the $base filename. 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.

COPYRIGHT
       Copyright (c) 2004 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.

       Please submit bug reports and patches to perlbug@perl.org.


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+-----------------------+
       |ATTRIBUTE TYPE |   ATTRIBUTE VALUE     |
       +---------------+-----------------------+
       |Availability   | runtime/perl-532      |
       +---------------+-----------------------+
       |Stability      | Pass-through volatile |
       +---------------+-----------------------+

SEE ALSO
       File::Spec



NOTES
       Source code for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from
       http://www.cpan.org/src/5.0/perl-5.32.0.tar.gz.

       Further information about this software can be found on the open source
       community website at https://www.perl.org/.



perl v5.32.0                      2020-06-14               File::Spec::Unix(3)