Linux extension permissions

Linux extension permission default permission each terminal has an umask attribute to determine the default permission for creating a new file umask indicates that the default permission for the directory is: 777-umask the default permission for the file is: 666-umask is generally used. the default umask of common users is 002, and the root user's mo... linux extension permission default permission each terminal has an umask attribute to determine the default permission for creating a new file umask indicates that the default permission for the directory is: 777-umask the default permission for the file is: 666-umask is generally used. the default umask of a common user is 002, and the default umask of a root user is 022. umask is used to view and set the special permissions of umask values, except for general permissions, there are also effects of special permissions on files on directories. suid is executed as the user to which the file belongs, the user without the execution file does not have the sgid to execute as the file owner group. the group to which the new file is created in the directory is the same as the group to which the file belongs. the user without the write permission to the directory can only delete the sticky. its files, you cannot delete files owned by other users. set special permissions to chmod u + s file. set suidchmod g + s dir. set sgidchmod o + t dir. set sticky. you can change the special permissions to SUID = 4. SGID = 2 STICKY = 1