Synopsis:
   $mkdir(<directory> [<directory> ...])

Technical:
   This function adds the following directories to the filesystem, using
   the mkdir(3) library call.  The default permissions are 0777, minus
   the current umask value.  Any number of directories may be created at
   once.  Tilde-expansion is permitted.

Practical:
   This function creates one or more new directories.  It is probably most
   useful for script installers.  Make sure you set your umask correctly,
   otherwise you may inadvertently create the directory with permissions
   that allow anyone to write to it.

Returns:
   > 0   number of directories that could not be created
     0   success

Examples:
   $mkdir(~/myscript)                probably returns "0"
   $mkdir(~/myscript /etc/hackerz)   probably returns "1"

See Also:
   chmod(6); rmdir(6); umask(6)