use strict;
use File::Find;
my $dir = "/some/dir/in/linux";
File::Find::find (\&search, $dir);

sub search {
if (-f $_) {
print "$_\n";
}
}

##</code><code>##

5a.xml
1b.xml
67.xml
1B.xml

##</code><code>##

1b.xml
1B.xml
5a.xml
67.xml