Reading and Getting Help
Read any text file, never type a long command twice, and work out a command you've never seen.
Updated
Reading
- Reading Files: cat and less (Novice): cat prints a short file on the screen, less shows a long one a screen at a time with keys to move and search, and file tells you what kind of file something is before you open it.
Remembering
- Your Command History (Apprentice): The shell remembers every command you type, so the up arrow brings back the last ones, history lists them all with numbers, Ctrl+R finds one by any part of it, and clear gives you a fresh screen.
Help
- Getting Help (Apprentice): Every command can explain itself, with --help for a short list of its options and man for its full manual page, type and which tell you what kind of command a name is, and an error message says what went wrong when you read it one part at a time.
Exercise: Read the Logbook
- Exercise: Read the Logbook (Apprentice): Take over a lighthouse station by reading its notice, its long logbook and its supplies with cat, less and file, look up a new command in its manual page, and let a check script tell you which answers are right.