Multiple choice technology programming languages

Built in Variable to tell you the PID of last started background process

  1. $$
  2. $#
  3. $_
  4. $!
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The special shell variable $! expands to the process ID of the most recently executed background (asynchronous) command. In contrast, $$ represents the PID of the current shell, $# is the number of positional parameters, and $_ holds the last argument of the previous command.