# create a filehandle to the directory - check for errors
opendir (DIR, "path/to/directory") or die "Unable to open directory: $!";

# read in all file names except . and ..
@files = grep {$_ ne "." && $_ ne ".."} readdir (DIR);

# close the filehandle to the directory
closedir (DIR);

# do whatever you want with filenames in @files