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. Usually used in .login or .profile. umask is available as a built-in command in the Bourne and C shells (see Sections 4 and 5).

umask Number	File Permission	Directory 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.