27 File permissions ******************* Each file has a set of “file mode bits” that control the kinds of access that users have to that file. They can be represented either in symbolic form or as an octal number.
· Mode Structure Structure of file mode bits. · Symbolic Modes Mnemonic representation of file mode bits. · Numeric Modes File mode bits as octal numbers. · Operator Numeric Modes ANDing, ORing, and setting modes octally. · Directory Setuid and Setgid Set-user-ID and set-group-ID on directories.