Unix Permissions Cheat-Sheet
Outcome Understand how rwx maps to octal digits. Set, fix, and audit permissions quickly using: chmod chown setfacl Remember what SUID / SGID / sticky and ACL do without Googling. Permissions Basics Octal Symbolic Meaning 0 --- No rights 1 --x Execute only 2 -w- Write only 3 -wx Write + Execute 4 r-- Read only 5 r-x Read + Execute 6 rw- Read + Write 7 rwx Read + Write + Execute Mnemonic: 421 $\rightarrow$ rwx ...