Linux File Permissions — chmod(numeric) calculator

Linux is a multi-user operating system. Every piece of data in Linux is a file. Linux File System assigns roles and permissions on each file/directory.

The file owner/root can change these permissions using the chmod command.

Usage: chmod [OPTIONS] MODE FILE //The mode can be numeric or symbolic.

Chmod permission bit calculator

The user roles are:

• Owner: User who owns the file.
• Group: The Group (and the users in this group) who have the same access permissions on the file.
• Other: All other users who are neither owners nor belong to the group.

The permissions are:

• Read (r): Assigned users can just open and read the file.
• Write (w): Can write(edit) to the file.
• Execute (x): Can run a shell script or an executable.

Use the ls command to view the permissions on any file/directory.

>ls -lt //Long listing of files in a directory

Each file is owned by user “divya” and belongs to the “staff” group.