


File::Spec::Mac(3Perl Programmers Reference GuFile::Spec::Mac(3p)


NAME
       File::Spec::Mac - File::Spec for MacOS

SYNOPSIS
        require File::Spec::Mac; # Done internally by File::Spec if needed


DESCRIPTION
       Methods for manipulating file specifications.

METHODS
       canonpath
         On MacOS, there's nothing to be done.  Returns what it's
         given.

       catdir
         Concatenate two or more directory names to form a com-
         plete path ending with a directory.  Put a trailing : on
         the end of the complete path if there isn't one, because
         that's what's done in MacPerl's environment.

         The fundamental requirement of this routine is that

                   File::Spec->catdir(split(":",$path)) eq $path

         But because of the nature of Macintosh paths, some addi-
         tional possibilities are allowed to make using this rou-
         tine give reasonable results for some common situations.
         Here are the rules that are used.  Each argument has its
         trailing ":" removed.  Each argument, except the first,
         has its leading ":" removed.  They are then joined
         together by a ":".

         So

                   File::Spec->catdir("a","b") = "a:b:"
                   File::Spec->catdir("a:",":b") = "a:b:"
                   File::Spec->catdir("a:","b") = "a:b:"
                   File::Spec->catdir("a",":b") = "a:b"
                   File::Spec->catdir("a","","b") = "a::b"

         etc.

         To get a relative path (one beginning with :), begin the
         first argument with : or put a "" as the first argument.

         If you don't want to worry about these rules, never
         allow a ":" on the ends of any of the arguments except
         at the beginning of the first.

         Under MacPerl, there is an additional ambiguity.  Does
         the user intend that

                   File::Spec->catfile("LWP","Protocol","http.pm")



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File::Spec::Mac(3Perl Programmers Reference GuFile::Spec::Mac(3p)


         be relative or absolute?  There's no way of telling
         except by checking for the existence of LWP: or :LWP,
         and even there he may mean a dismounted volume or a rel-
         ative path in a different directory (like in @INC).   So
         those checks aren't done here. This routine will treat
         this as absolute.

       catfile
         Concatenate one or more directory names and a filename
         to form a complete path ending with a filename.  Since
         this uses catdir, the same caveats apply.  Note that the
         leading : is removed from the filename, so that

                   File::Spec->catfile($ENV{HOME},"file");

         and

                   File::Spec->catfile($ENV{HOME},":file");

         give the same answer, as one might expect.

       curdir
         Returns a string representing the current directory.

       devnull
         Returns a string representing the null device.

       rootdir
         Returns a string representing the root directory.  Under
         MacPerl, returns the name of the startup volume, since
         that's the closest in concept, although other volumes
         aren't rooted there.

       tmpdir
         Returns a string representation of the first existing
         directory from the following list or '' if none exist:

             $ENV{TMPDIR}


       updir
         Returns a string representing the parent directory.

       file_name_is_absolute
         Takes as argument a path and returns true, if it is an
         absolute path.  In the case where a name can be either
         relative or absolute (for example, a folder named "HD"
         in the current working directory on a drive named "HD"),
         relative wins.  Use ":" in the appropriate place in the
         path if you want to distinguish unambiguously.

       path
         Returns the null list for the MacPerl application, since
         the concept is usually meaningless under MacOS. But if



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File::Spec::Mac(3Perl Programmers Reference GuFile::Spec::Mac(3p)


         you're using the MacPerl tool under MPW, it gives back
         $ENV{Commands} suitably split, as is done in :lib:ExtU-
         tils:MM_Mac.pm.

       splitpath

       splitdir

       catpath

       abs2rel

       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 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
         $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 the canonpath() entry elsewhere in this document.

         Based on code written by Shigio Yamaguchi.

         No checks against the filesystem are made.

SEE ALSO
       the File::Spec manpage















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