Using umask in perl

The easiest way to use umask in perl is with octal notation


  umask 077;

  # open newfile with permissions rw- --- ---
  open PRIVATE, ">newfile" or die;

  # create new directory with permissions rwx --- ---
  mkdir "newdir" or die;

  # mkdir is modified by umask, so this will create
  # the dir with at most 0700 perms.
  mkdir "newdir2", 0700  or die;