Concatenate two or more directory names to form a complete 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 additional
possibilities are allowed to make using this routine 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")
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 relative path in a different directory (like in @INC). So those checks
aren't done here. This routine will treat this as absolute.
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.