umask [nnn]umask [-S] [mask]Display file creation mask or set file creation mask to octal value nnn. The file creation mask determines which permission bits are turned off (e.g., umask 002 produces rw-rw-r--). See the entry in Chapter 2 for examples.
The second form is specific to ksh93. A symbolic mask is permissions to keep.
-SPrint the current mask using symbolic notation. ksh93 only.