Linux umask command details how to use Linux umask command

Umask can be used to set the [permission mask]. The [permission mask] is composed of three octal numbers. After the existing access permissions are removed from the permission mask, the preset permissions for file creation can be generated.

Syntax

Umask [-S] [permission mask]

Parameter description:

-S indicates the permission mask in text format.

Instance

Run the following command to view the current permission mask:

$ Umask # obtain the current permission mask

After executing the preceding command, the output information is as follows:

0022

Next, run the command "mkdir" to create a directory and run the command "ls" to obtain detailed information about the directory. Enter the following command:

$ Mkdir test1 # Create a directory $ ls-d-l test1/# display the directory details

After executing the preceding command, the detailed information of the newly created directory is displayed, as shown below:

Drwxr-xr-x 2 rootlocal 4096 2011-9-19 test1/

Note: In the preceding output, "drwxr-xr-x" = "777-022 = 755 ".