RHCSA Rapid Track

The chmod command changes file permissions from the command line.

The chmod command can use one of two methods to represent permissions: symbolic or octal.

The chown command changes file ownership. The chown command -R option recursively changes the ownership of a directory tree.

The umask command without arguments displays the current umask value of the shell. Every process on the system has a umask.

The default umask values for Bash are defined in the /etc/login.defs file and might be affected by settings in the /etc/profile and /etc/bashrc files, files in /etc/profile.d, or your account's shell initialization files.

The suid, sgid, and sticky special permissions provide additional access-related features to files.