Retrieving a List of directories only

blackadder has asked for the wisdom of the Perl Monks concerning the following question:

Greetings Monks

I have the following code:

use strict;
use File::Find;
my $path = shift @ARGV;
my @dirs;
find (sub {push @dirs, $File::Find::dir}, $path);
foreach my $dir (@dirs){
    print "$dir\n";}
[download]

It’s meant to obtain a list of directories. However when running this script it takes ages to populate the array with entries. And most of the directories are duplicated number of times. Does any one know the reason for this and is there a better way to obtain a list of directories quicker than this very slow method.
Many Thanks in advance.

Comment on Retrieving a List of directories only Download Code

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•Re: Retrieving a List of directories only by merlyn (Sage) on Jul 29, 2002 at 14:28 UTC
You're getting the directories for every file entry. You need to reject anything that isn't named "dot", then take the directory from which that's located: `find (sub {push @dirs, $File::Find::dir if $_ eq "."}, $path);` [download] -- Randal L. Schwartz, Perl hacker	[reply] [d/l]
Re: Retrieving a List of directories only by Abigail-II (Bishop) on Jul 29, 2002 at 14:35 UTC
Your sub is called for each encountered file or directory. So, if a directory has 5 files in them, you push the directory 5 times on the array. You need something like (untested): `find (sub {push @dirs => $File::Find::name if -d});` [download] The fact that it takes "ages" is that it's going to traverse your entire file hierarchy. If you have a million files, the sub will be called a million times. Abigail	[reply] [d/l]
Re: Retrieving a List of directories only by broquaint (Abbot) on Jul 29, 2002 at 15:24 UTC
What a wonderful excuse to use the new and oh so shiny `File::Find::Rule` `use File::Find::Rule; my @dirs = find(directory => , in => shift @ARGV);` [download] That will find all the subdirectories the given directory. HTH `_________ broquaint`	[reply] [d/l]
Re: Retrieving a List of directories only by particle (Vicar) on Jul 29, 2002 at 14:42 UTC
this accepts multiple arguments,and uses a hash to build a unique directory list. `#!/usr/bin/perl require 5.006; use strict; use warnings; $\|++; use File::Find (); my %dirs; while( $_ = shift @ARGV ) { next unless -d $_; File::Find::find sub{ -d $File::Find::name and $dirs{$File::Find::name} = undef }, $_; } print $_,$/ for sort keys %dirs;` [download] ~Particle accelerates	[reply] [d/l] [select]
Re: Re: Retrieving a List of directories only by blackadder (Hermit) on Jul 29, 2002 at 15:14 UTC
Chaps and chapetts...You are all Brilliant. Thanks for this. PS : Any Chanse of help in my Drag and Drop problems,...please.	[reply]