while (defined ($jobdir = readdir(DIR)))  {
      next if $jobdir eq "." or $jobdir eq "..";
      next unless -d $jobdir;
      print "$jobdir\n";
}

output:

while (defined ($jobdir = readdir(DIR)))  {
      next if $jobdir eq "." or $jobdir eq "..";
      #next unless -d $jobdir;
      print "$jobdir\n";
}

output:
testdir
testdir2
testfile