How can I recursively read out directories in Perl? - perl

Question

I want to read out a directory recursively to print the data-structure in an HTML-Page with Template::Toolkit.
But I'm hanging in how to save the Paths and Files in a form that can be read our easy.
My idea started like this
sub list_dirs{
my ($rootPath) = #_;
my (#paths);
$rootPath .= '/' if($rootPath !~ /\/$/);
for my $eachFile (glob($path.'*'))
{
if(-d $eachFile)
{
push (#paths, $eachFile);
&list_dirs($eachFile);
}
else
{
push (#files, $eachFile);
}
}
return #paths;
}
How could I solve this problem?

Answer 1

This should do the trick
use strict;
use warnings;
use File::Find qw(finddepth);
my #files;
finddepth(sub {
return if($_ eq '.' || $_ eq '..');
push #files, $File::Find::name;
}, '/my/dir/to/search');

Answer 2

You should always use strict and warnings to help you debug your code. Perl would have warned you for example that #files is not declared. But the real problem with your function is that you declare a lexical variable #paths on every recursive call to list_dirs and don't push the return value back after the recursion step.
push #paths, list_dir($eachFile)
If you don't want to install additional modules, the following solution should probably help you:
use strict;
use warnings;
use File::Find qw(find);
sub list_dirs {
my #dirs = #_;
my #files;
find({ wanted => sub { push #files, $_ } , no_chdir => 1 }, #dirs);
return #files;
}

Answer 3

The answer by mdom explains how your initial attempt went astray. I would also suggest that you consider friendlier alternatives to File::Find. CPAN has several options. Here's one.
use strict;
use warnings;
use File::Find::Rule;
my #paths = File::Find::Rule->in(#ARGV);
Also see here:
SO answer providing CPAN
alternatives to File::Find.
SO question on directory iterators.
And here is a rewrite of your recursive solution. Things to note: use strict; use warnings; and the use of a scoping block to create a static variable for the subroutine.
use strict;
use warnings;
print $_, "\n" for dir_listing(#ARGV);
{
my #paths;
sub dir_listing {
my ($root) = #_;
$root .= '/' unless $root =~ /\/$/;
for my $f (glob "$root*"){
push #paths, $f;
dir_listing($f) if -d $f;
}
return #paths;
}
}

Answer 4

I think you have problem in the following line in your code
for my $eachFile (glob($path.'*'))
You change the $path variable into $rootpath.
It will store the path correctly.

Answer 5

I use this script to remove hidden files (created by Mac OS X) from my USB Pendrive, where I usually use it to listen music in the car, and any file ending with ".mp3", even when it starts with "._", will be listed in the car audio list.
#!/bin/perl
use strict;
use warnings;
use File::Find qw(find);
sub list_dirs {
my #dirs = #_;
my #files;
find({ wanted => sub { push #files, $_ } , no_chdir => 1 }, #dirs);
return #files;
}
if ( ! #ARGV || !$ARGV[0] ) {
print "** Invalid dir!\n";
exit ;
}
if ( $ARGV[0] !~ /\/Volumes\/\w/s ) {
print "** Dir should be at /Volume/... > $ARGV[0]\n";
exit ;
}
my #paths = list_dirs($ARGV[0]) ;
foreach my $file (#paths) {
my ($filename) = ( $file =~ /([^\\\/]+)$/s ) ;
if ($filename =~ /^\._/s ) {
unlink $file ;
print "rm> $file\n" ;
}
}

Answer 6

you can use this method as recursive file search that separate specific file types,
my #files;
push #files, list_dir($outputDir);
sub list_dir {
my #dirs = #_;
my #files;
find({ wanted => sub { push #files, glob "\"$_/*.txt\"" } , no_chdir => 1 }, #dirs);
return #files;
}