


File::Spec::Unix(Perl Programmers Reference GFile::Spec::Unix(3p)


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 ) ;


       catdir
         Concatenate two or more directory names to form a com-
         plete 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 direc-
         tory.  "." 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.



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File::Spec::Unix(Perl Programmers Reference GFile::Spec::Unix(3p)


         ".." 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, or OS/2.  It does sometimes on MacOS (see the
         file_name_is_absolute entry in the File::Spec::MacOS
         manpage).  It does consult the working environment for
         VMS (see the file_name_is_absolute entry in the
         File::Spec::VMS manpage).

       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 por-
         tions. 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 the catpath() entry else-
         where in this document to get back a path equivalent to
         (usually identical to) the original path.

       splitdir
         The opposite of the catdir() entry elsewhere in this
         document.



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File::Spec::Unix(Perl Programmers Reference GFile::Spec::Unix(3p)


             @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 (e.g. MacOS).

         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 direc-
         tory and file are catenated.  A '/' is inserted if need
         be.  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 desti-
         nation path:

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

         If $base is not present or '', then the cwd() entry
         elsewhere in this document is used. If $base is rela-
         tive, then it is converted to absolute form using the
         rel2abs() entry elsewhere in this document. This means
         that it is taken to be relative to the cwd() entry else-
         where in this document.

         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 the rel2abs() entry elsewhere in this document.
         This means that it is taken to be relative to the cwd()
         entry elsewhere in this document.




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File::Spec::Unix(Perl Programmers Reference GFile::Spec::Unix(3p)


         No checks against the filesystem are made on most sys-
         tems.  On MacOS, the filesystem may be consulted (see
         the file_name_is_absolute entry in the File::Spec::MacOS
         manpage).  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 the cwd() entry
         elsewhere in this document is used. If $base is rela-
         tive, then it is converted to absolute form using the
         rel2abs() entry elsewhere in this document. This means
         that it is taken to be relative to the cwd() entry else-
         where in this document.

         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 the canonpath() entry elsewhere in this document.

         No checks against the filesystem are made on most sys-
         tems.  On MacOS, the filesystem may be consulted (see
         the file_name_is_absolute entry in the File::Spec::MacOS
         manpage).  On VMS, there is interaction with the working
         environment, as logicals and macros are expanded.

         Based on code written by Shigio Yamaguchi.

SEE ALSO
       the File::Spec manpage















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