CompTIA Linux+ Certification Practice Exam 2026 - Free Linux+ Practice Questions and Study Guide

The command that changes file permissions in Linux is "chmod." This command allows users to modify the access permissions of files and directories. It can set permissions for the owner of the file, the group associated with the file, and others (everyone else).

Using "chmod," you can specify the permissions in numeric format (for example, 755) or symbolic format (like using 'r' for read, 'w' for write, and 'x' for execute) to grant or restrict access appropriately. By adjusting these settings, you can control who can read, write, or execute a file, which is essential for maintaining security and proper access controls on a Linux system.

Other options listed do have specific functions related to file management: "chown" changes the ownership of a file but does not affect permissions; "chperm" is not a standard command in Linux; and "setfacl" modifies access control lists for more granular permissions management but is not used to change traditional file permissions directly in the same way that "chmod" does.