How can I loop through files in a directory in Perl?

Question

Possible Duplicate:
How can I list all of the files in a directory with Perl?

I want to loop through a few hundred files that are all contained in the same directory. How would I do this in Perl?

Isn't this question a duplicated of this one? http://stackoverflow.com/questions/1045792/how-can-i-list-all-of-the-files-in-a-directory-with-perl — Leonardo Herrera, Jan 27 '10 at 18:35
@Leonardo Herrera Indeed, it is. Sorry, I did not remember that one. Voting to close. — Sinan Ünür, Jan 27 '10 at 18:36
I don't see how this is a duplicate. The question asks how to loop through files in a directory. The marked 'duplicate' asks how to list all the files in a directory. Clearly different. Why mark as a duplicate? — CJ7, Feb 15 '16 at 00:33

score 53 · Answer 1 · edited Feb 19 '19 at 01:13

53

#!/usr/bin/perl -w

my @files = <*>;
foreach my $file (@files) {
  print $file . "\n";
}

Where

 @files = <*>;

can be

 @files = </var/www/htdocs/*>;
 @files = </var/www/htdocs/*.html>;

etc.

edited Feb 19 '19 at 01:13

Sam B

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answered Jan 27 '10 at 18:32

EToreo

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This will not list hidden files (those starting with a dot) on GNU/Linux and probably other similar operating systems. – josch Dec 22 '16 at 16:07

score 23 · Answer 2 · edited Aug 07 '12 at 12:42

23

Enjoy.

opendir(DH, "directory");
my @files = readdir(DH);
closedir(DH);

foreach my $file (@files)
{
    # skip . and ..
    next if($file =~ /^\.$/);
    next if($file =~ /^\.\.$/);

    # $file is the file used on this iteration of the loop
}

edited Aug 07 '12 at 12:42

Community

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answered Jan 27 '10 at 18:32

skarface

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thanks! I'd use `next if ($file =~ /^.+$/);` though, to avoid the second statement ;) . – ashraf Mar 24 '15 at 18:03
2

@ashraf regex has to be /^\.+$/ instead of /^.+$/ – Rauf Aug 06 '17 at 13:31
@Rauf yes I think you're right! :) – ashraf Aug 07 '17 at 12:53

Sinan Ünür · Answer 3 · 2015-05-11T14:23:35.823

You can use readdir or glob.

Or, you can use a module such as Path::Class:

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

Or, Path::Tiny:

@paths = path("/tmp")->children;
@paths = path("/tmp")->children( qr/\.txt$/ );
Returns a list of Path::Tiny objects for all files and directories within a directory. Excludes "." and ".." automatically.

If an optional qr// argument is provided, it only returns objects for child names that match the given regular expression. Only the base name is used for matching:

@paths = path("/tmp")->children( qr/^foo/ );
# matches children like the glob foo*

Getting the list of directory entries into an array wastes some memory (as opposed to getting one file name at a time), but with only a few hundred files, this is unlikely to be an issue.

Path::Class is portable to operating systems other than *nix and Windows. On the other hand, AFAIK, its instances use more memory than do Path::Tiny instances.

If memory is an issue, you are better off using readdir in a while loop.

and reead_dir removes . and .. for you, and if need be can prefix the directory into the filename — Matthew Lock, Aug 04 '14 at 07:26

How can I loop through files in a directory in Perl?

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