umask

umask [value]

Print the current value of the file creation mode mask, or set it to value, a three-digit octal code specifying the read-write-execute permissions to be turned off. This is the opposite of chmod. Normally used in .login or .profile. umask is a built-in command in the Bourne, Korn, and C shells (see Chapter 4 and Chapter 5).

umask	File	Directory
Number	Permission	Permission
0	rw-	rwx
1	rw-	rw-
2	r--	r-x
3	r--	r--
4	-w-	-wx
5	-w-	-w-
6	---	--x
7	---	---

Examples

Turn off write permission for others:

umask 002		Produces file permission -rw-rw-r--

Turn off all permissions for group and others:

umask 077		Produces file permission -rw-------

Note that you can omit leading zeroes.