User's file creation mask. Set the shell process's file creation mask to mode.
Syntax
umask [-p] [-S] [mode]
Key
mode File creation mask
-S Print the mask in symbolic format (the default is an octal number)
-p Output in a form that may be reused as input (if mode is omitted)
The current value of the mask will be printed if mode is omitted. By default OS X will set it to 0022 (022)
If mode begins with a digit, it is interpreted as an octal number; otherwise it is interpreted as a symbolic mode mask similar to that accepted by chmod.
Note that when the mode is interpreted as an octal number, each number of the umask is subtracted from 7. Thus, a umask of 022 results in permissions of 755.
The return status is 0 if the mode was successfully changed or if no mode argument was supplied, and false otherwise.
Examples
Example values for the mask:
022, gives read and execute access to the group and others.
The return status is zero if the mode is successfully changed or if no mode
argument is supplied, and non-zero otherwise.
Note that when the mode is interpreted as an octal number, each number of the
umask is subtracted from 7. Thus, a umask of 022 results
in permissions of 755.
umask is a bash built in command.
"Woe to him who doesn't know how to wear his mask, be he king or Pope!"
- Luigi Pirandello
Related:
chmod - Change access permissions
chown - Change file owner and group
