Programming the Shell

• Programming the Shells
  • Introduction
    • Bourne - C shell comparisons
    • Variables
  • A Simple Script
    • Running the Script
  • Special Characters
    • '...': Turn off Meaning of Special Characters.
    • "...": Turn off Meaning of Special Characters EXCEPT $ and `
    • `...`: Use Output as Content of Variable
  • Verbatim echo
  • Parameters and the Shell
    • $0: The Name of the Invoking Command
    • $1 $2 $3 ... $9, $*: Shell Parameters
    • $#: Number of Parameters
    • shift: Shifts Parameters
  • read: Reading Input from User
  • test: Comparisons
    • Testing/Comparing Numbers
    • Verifying File Types
    • Comparing Strings
    • Combining test: Expressions
  • Control Structures
    • for var in list
    • while condition
    • until loop
    • if statement
    • case: Selections
  • expr: Doing Arithmetic
  • Subroutines
  • Miscellaneous
    • break
    • $$: Process ID
    • $!: PID (Process ID) of the previous background command
    • $: Return Code
    • A || B: Either or
    • A && B: Both or Nothing
    • set: Change Command-line Parameters
  • trap: Trap signals
  • Tips Using Shell Commands
    • basename: Current Directory
    • dirname: Directory Path
    • stty -echo: Passwords
    • cut, awk: Cut Selected Fields
  • Exercises