The entries . and .. are created by the operating system and will always exist in every directory. Normally the command that lists the files in a directory (e.g. ls on Unix systems or dir on Windows) doesn't show them, but they are there nonetheless. It's the job of your script to ignore them.

One way is to simply test for them:

opendir(D, "/some/directory");
my @entries = readdir(D);
closedir(D);

for my $f (@entries) {
  next if ($f eq "." or $f eq "..");
  ...
}
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If you can safely ignore any files that begin with a dot, consider using glob() with a star:

my @entries = glob("/some/directory/*");
...
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A third way is to skip all entries that are not files:

opendir(D, "/some/dir");
my @entries = readdir(D);
closedir(D);
for my $f (@entries) {
  next unless -f "/some/dir/$f";
  ...
}
[download]