Be aware though that a glob might be slower than a loop: 
#!/usr/bin/perl

use strict;
use warnings;

use Benchmark qw( cmpthese );


sub globber {
    return(( glob '*.xml')[0]);
}
sub opener {
    opendir my $dir, '.';
    my $file;
    while (defined($file= readdir $dir)) {
        last if $file=~ /\.xml$/;
    }
    closedir $dir;
    return $file;
}
cmpthese(5000, {
   globber   => \&globber,
   opener  => \&opener,
});

[download]
          Rate globber  opener
globber  654/s      --    -76%
opener  2688/s    311%      --
s$$([},&%#}/&/]+}%&{})*;#$&&s&&$^X.($'^"%]=\&(|?*{%
+.+=%;.#_}\&"^"-+%*).}%:##%}={~=~:.")&e&&s""`$''`"e

In reply to Re^2: Pulling a file with a given extension by Skeeve
in thread Pulling a file with a given extension by rashley

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