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Path::Class::Dir(3)                  User Contributed Perl Documentation                 Path::Class::Dir(3)



NAME
       Path::Class::Dir - Objects representing directories

VERSION
       version 0.24

SYNOPSIS
         use Path::Class qw(dir);  # Export a short constructor

         my $dir = dir('foo', 'bar');       # Path::Class::Dir object
         my $dir = Path::Class::Dir->new('foo', 'bar');  # Same thing

         # Stringifies to 'foo/bar' on Unix, 'foo\bar' on Windows, etc.
         print "dir: $dir\n";

         if ($dir->is_absolute) { ... }
         if ($dir->is_relative) { ... }

         my $v = $dir->volume; # Could be 'C:' on Windows, empty string
                               # on Unix, 'Macintosh HD:' on Mac OS

         $dir->cleanup; # Perform logical cleanup of pathname
         $dir->resolve; # Perform physical cleanup of pathname

         my $file = $dir->file('file.txt'); # A file in this directory
         my $subdir = $dir->subdir('george'); # A subdirectory
         my $parent = $dir->parent; # The parent directory, 'foo'

         my $abs = $dir->absolute; # Transform to absolute path
         my $rel = $abs->relative; # Transform to relative path
         my $rel = $abs->relative('/foo'); # Relative to /foo

         print $dir->as_foreign('Mac');   # :foo:bar:
         print $dir->as_foreign('Win32'); #  foo\bar

         # Iterate with IO::Dir methods:
         my $handle = $dir->open;
         while (my $file = $handle->read) {
           $file = $dir->file($file);  # Turn into Path::Class::File object
           ...
         }

         # Iterate with Path::Class methods:
         while (my $file = $dir->next) {
           # $file is a Path::Class::File or Path::Class::Dir object
           ...
         }

DESCRIPTION
       The "Path::Class::Dir" class contains functionality for manipulating directory names in a cross-platform crossplatform
       platform way.

METHODS
       $dir = Path::Class::Dir->new( <dir1>, <dir2>, ... )
       $dir = dir( <dir1>, <dir2>, ... )
           Creates a new "Path::Class::Dir" object and returns it.  The arguments specify names of
           directories which will be joined to create a single directory object.  A volume may also be
           specified as the first argument, or as part of the first argument.  You can use platform-neutral
           syntax:

             my $dir = dir( 'foo', 'bar', 'baz' );

           or platform-native syntax:

             my $dir = dir( 'foo/bar/baz' );

           or a mixture of the two:

             my $dir = dir( 'foo/bar', 'baz' );

           All three of the above examples create relative paths.  To create an absolute path, either use
           the platform native syntax for doing so:

             my $dir = dir( '/var/tmp' );

           or use an empty string as the first argument:

             my $dir = dir( '', 'var', 'tmp' );

           If the second form seems awkward, that's somewhat intentional - paths like "/var/tmp" or
           "\Windows" aren't cross-platform concepts in the first place (many non-Unix platforms don't have
           a notion of a "root directory"), so they probably shouldn't appear in your code if you're trying
           to be cross-platform.  The first form is perfectly natural, because paths like this may come from
           config files, user input, or whatever.

           As a special case, since it doesn't otherwise mean anything useful and it's convenient to define
           this way, "Path::Class::Dir->new()" (or "dir()") refers to the current directory
           ("File::Spec->curdir").  To get the current directory as an absolute path, do "dir()->absolute".

           Finally, as another special case "dir(undef)" will return undef, since that's usually an accident
           on the part of the caller, and returning the root directory would be a nasty surprise just asking
           for trouble a few lines later.

       $dir->stringify
           This method is called internally when a "Path::Class::Dir" object is used in a string context, so
           the following are equivalent:

             $string = $dir->stringify;
             $string = "$dir";

       $dir->volume
           Returns the volume (e.g. "C:" on Windows, "Macintosh HD:" on Mac OS, etc.) of the directory
           object, if any.  Otherwise, returns the empty string.

       $dir->is_dir
           Returns a boolean value indicating whether this object represents a directory.  Not surprisingly,
           "Path::Class::File" objects always return false, and "Path::Class::Dir" objects always return
           true.

       $dir->is_absolute
           Returns true or false depending on whether the directory refers to an absolute path specifier
           (like "/usr/local" or "\Windows").

       $dir->is_relative
           Returns true or false depending on whether the directory refers to a relative path specifier
           (like "lib/foo" or "./dir").

       $dir->cleanup
           Performs a logical cleanup of the file path.  For instance:

             my $dir = dir('/foo//baz/./foo')->cleanup;
             # $dir now represents '/foo/baz/foo';

       $dir->resolve
           Performs a physical cleanup of the file path.  For instance:

             my $dir = dir('/foo//baz/../foo')->resolve;
             # $dir now represents '/foo/foo', assuming no symlinks

           This actually consults the filesystem to verify the validity of the path.

       $file = $dir->file( <dir1>, <dir2>, ..., <file> )
           Returns a "Path::Class::File" object representing an entry in $dir or one of its subdirectories.
           Internally, this just calls "Path::Class::File->new( @_ )".

       $subdir = $dir->subdir( <dir1>, <dir2>, ... )
           Returns a new "Path::Class::Dir" object representing a subdirectory of $dir.

       $parent = $dir->parent
           Returns the parent directory of $dir.  Note that this is the logical parent, not necessarily the
           physical parent.  It really means we just chop off entries from the end of the directory list
           until we cain't chop no more.  If the directory is relative, we start using the relative forms of
           parent directories.

           The following code demonstrates the behavior on absolute and relative directories:

             $dir = dir('/foo/bar');
             for (1..6) {
               print "Absolute: $dir\n";
               $dir = $dir->parent;
             }

             $dir = dir('foo/bar');
             for (1..6) {
               print "Relative: $dir\n";
               $dir = $dir->parent;
             }

             ########### Output on Unix ################
             Absolute: /foo/bar
             Absolute: /foo
             Absolute: /
             Absolute: /
             Absolute: /
             Absolute: /
             Relative: foo/bar
             Relative: foo
             Relative: .
             Relative: ..
             Relative: ../..
             Relative: ../../..

       @list = $dir->children
           Returns a list of "Path::Class::File" and/or "Path::Class::Dir" objects listed in this directory,
           or in scalar context the number of such objects.  Obviously, it is necessary for $dir to exist
           and be readable in order to find its children.

           Note that the children are returned as subdirectories of $dir, i.e. the children of foo will be
           foo/bar and foo/baz, not bar and baz.

           Ordinarily "children()" will not include the self and parent entries "." and ".." (or their
           equivalents on non-Unix systems), because that's like I'm-my-own-grandpa business.  If you do
           want all directory entries including these special ones, pass a true value for the "all"
           parameter:

             @c = $dir->children(); # Just the children
             @c = $dir->children(all => 1); # All entries

           In addition, there's a "no_hidden" parameter that will exclude all normally "hidden" entries - on
           Unix this means excluding all entries that begin with a dot ("."):

             @c = $dir->children(no_hidden => 1); # Just normally-visible entries

       $abs = $dir->absolute
           Returns a "Path::Class::Dir" object representing $dir as an absolute path.  An optional argument,
           given as either a string or a "Path::Class::Dir" object, specifies the directory to use as the
           base of relativity - otherwise the current working directory will be used.

       $rel = $dir->relative
           Returns a "Path::Class::Dir" object representing $dir as a relative path.  An optional argument,
           given as either a string or a "Path::Class::Dir" object, specifies the directory to use as the
           base of relativity - otherwise the current working directory will be used.

       $boolean = $dir->subsumes($other)
           Returns true if this directory spec subsumes the other spec, and false otherwise.  Think of
           "subsumes" as "contains", but we only look at the specs, not whether $dir actually contains
           $other on the filesystem.

           The $other argument may be a "Path::Class::Dir" object, a "Path::Class::File" object, or a
           string.  In the latter case, we assume it's a directory.

             # Examples:
             dir('foo/bar' )->subsumes(dir('foo/bar/baz'))  # True
             dir('/foo/bar')->subsumes(dir('/foo/bar/baz')) # True
             dir('foo/bar' )->subsumes(dir('bar/baz'))      # False
             dir('/foo/bar')->subsumes(dir('foo/bar'))      # False

       $boolean = $dir->contains($other)
           Returns true if this directory actually contains $other on the filesystem.  $other doesn't have
           to be a direct child of $dir, it just has to be subsumed.

       $foreign = $dir->as_foreign($type)
           Returns a "Path::Class::Dir" object representing $dir as it would be specified on a system of
           type $type.  Known types include "Unix", "Win32", "Mac", "VMS", and "OS2", i.e. anything for
           which there is a subclass of "File::Spec".

           Any generated objects (subdirectories, files, parents, etc.) will also retain this type.

       $foreign = Path::Class::Dir->new_foreign($type, @args)
           Returns a "Path::Class::Dir" object representing $dir as it would be specified on a system of
           type $type.  Known types include "Unix", "Win32", "Mac", "VMS", and "OS2", i.e. anything for
           which there is a subclass of "File::Spec".

           The arguments in @args are the same as they would be specified in "new()".

       @list = $dir->dir_list([OFFSET, [LENGTH]])
           Returns the list of strings internally representing this directory structure.  Each successive
           member of the list is understood to be an entry in its predecessor's directory list.  By
           contract, "Path::Class->new( $dir->dir_list )" should be equivalent to $dir.

           The semantics of this method are similar to Perl's "splice" or "substr" functions; they return
           "LENGTH" elements starting at "OFFSET".  If "LENGTH" is omitted, returns all the elements
           starting at "OFFSET" up to the end of the list.  If "LENGTH" is negative, returns the elements
           from "OFFSET" onward except for "-LENGTH" elements at the end.  If "OFFSET" is negative, it
           counts backward "OFFSET" elements from the end of the list.  If "OFFSET" and "LENGTH" are both
           omitted, the entire list is returned.

           In a scalar context, "dir_list()" with no arguments returns the number of entries in the
           directory list; "dir_list(OFFSET)" returns the single element at that offset; "dir_list(OFFSET,
           LENGTH)" returns the final element that would have been returned in a list context.

       $fh = $dir->open()
           Passes $dir to "IO::Dir->open" and returns the result as an "IO::Dir" object.  If the opening
           fails, "undef" is returned and $! is set.

       $dir->mkpath($verbose, $mode)
           Passes all arguments, including $dir, to "File::Path::mkpath()" and returns the result (a list of
           all directories created).

       $dir->rmtree($verbose, $cautious)
           Passes all arguments, including $dir, to "File::Path::rmtree()" and returns the result (the
           number of files successfully deleted).

       $dir->remove()
           Removes the directory, which must be empty.  Returns a boolean value indicating whether or not
           the directory was successfully removed.  This method is mainly provided for consistency with
           "Path::Class::File"'s "remove()" method.

       $dir->tempfile(...)
           An interface to "File::Temp"'s "tempfile()" function.  Just like that function, if you call this
           in a scalar context, the return value is the filehandle and the file is "unlink"ed as soon as
           possible (which is immediately on Unix-like platforms).  If called in a list context, the return
           values are the filehandle and the filename.

           The given directory is passed as the "DIR" parameter.

           Here's an example of pretty good usage which doesn't allow race conditions, won't leave yucky
           tempfiles around on your filesystem, etc.:

             my $fh = $dir->tempfile;
             print $fh "Here's some data...\n";
             seek($fh, 0, 0);
             while (<$fh>) { do something... }

           Or in combination with a "fork":

             my $fh = $dir->tempfile;
             print $fh "Here's some more data...\n";
             seek($fh, 0, 0);
             if ($pid=fork()) {
               wait;
             } else {
               something($_) while <$fh>;
             }

       $dir_or_file = $dir->next()
           A convenient way to iterate through directory contents.  The first time "next()" is called, it
           will "open()" the directory and read the first item from it, returning the result as a
           "Path::Class::Dir" or "Path::Class::File" object (depending, of course, on its actual type).
           Each subsequent call to "next()" will simply iterate over the directory's contents, until there
           are no more items in the directory, and then the undefined value is returned.  For example, to
           iterate over all the regular files in a directory:

             while (my $file = $dir->next) {
               next unless -f $file;
               my $fh = $file->open('r') or die "Can't read $file: $!";
               ...
             }

           If an error occurs when opening the directory (for instance, it doesn't exist or isn't readable),
           "next()" will throw an exception with the value of $!.

       $dir->recurse( callback => sub {...} )
           Iterates through this directory and all of its children, and all of its children's children,
           etc., calling the "callback" subroutine for each entry.  This is a lot like what the "File::Find"
           module does, and of course "File::Find" will work fine on "Path::Class" objects, but the
           advantage of the "recurse()" method is that it will also feed your callback routine "Path::Class"
           objects rather than just pathname strings.

           The "recurse()" method requires a "callback" parameter specifying the subroutine to invoke for
           each entry.  It will be passed the "Path::Class" object as its first argument.

           "recurse()" also accepts two boolean parameters, "depthfirst" and "preorder" that control the
           order of recursion.  The default is a preorder, breadth-first search, i.e. "depthfirst => 0,
           preorder => 1".  At the time of this writing, all combinations of these two parameters are
           supported except "depthfirst => 0, preorder => 0".

       $st = $file->stat()
           Invokes "File::stat::stat()" on this directory and returns a "File::stat" object representing the
           result.

       $st = $file->lstat()
           Same as "stat()", but if $file is a symbolic link, "lstat()" stats the link instead of the
           directory the link points to.

       $class = $file->file_class()
           Returns the class which should be used to create file objects.

           Generally overridden whenever this class is subclassed.

AUTHOR
       Ken Williams, kwilliams@cpan.org

SEE ALSO
       Path::Class, Path::Class::File, File::Spec



perl v5.12.5                                     2013-08-25                              Path::Class::Dir(3)