Question

I have a Ruby script (1.8.7) that sets up its own interactive shell for running specific commands.
I want to be able to exit when a user presses CTRL+D (mac/linux). The script just sits in a loop and uses Readline to read user input. I understand that CTRL+D sends the EOF control character but how do I test for this in Ruby? It doesn’t seem to be included in the lists of standard unix signals and since technically it isn’t a character, I’m guessing normal string comparison on the line won’t work either.

Any ideas / pointers / suggestions would be much appreciated

Cheers

Answer 1

From the documentation:

readline(prompt = “”, add_hist = false)

(…) Returns nil when the inputted line is empty and user inputs EOF (Presses ^D on UNIX).

Example:

require "readline"
while buf = Readline.readline("> ", true)
  p buf
end
puts "EOF received, exiting"