TestOut Linux Pro 2025 – 400 Free Practice Questions to Pass the Exam

The command to change the permissions of a file or directory in Linux is "chmod." This command stands for "change mode," which allows users to set who can read, write, or execute a file or directory. It is a fundamental command in Linux for managing access control and protecting files from unauthorized access.

When using chmod, permissions can be modified using either symbolic notation (like 'r' for read, 'w' for write, and 'x' for execute) or numeric/ octal notation (like 755). For instance, running "chmod 755 filename" would give the owner full permissions (read, write, and execute), while the group and others would have read and execute permissions only.

The other choices do not represent valid commands in the context of changing file or directory permissions. "Alter" is not a recognized command in Linux for this purpose, "setperm" is not a standard command, and "edit" does not change permissions at all; it typically refers to modifying the contents of a file rather than its access rights. Thus, "chmod" is the correct and standard command used for this function in Linux.