stdlib_libraries/pseudo_terminals_no_parens.rb

tests/_examples/stdlib_libraries/pseudo_terminals_no_parens.rb in the metorex repository.

# PTY runs a program with a terminal of its own and opens terminal pairs, and
# PTY.check reports on a child without waiting for it.
require "pty"
p PTY.singleton_methods.sort
p PTY::ChildExited.superclass

reader, writer, pid = PTY.spawn "printf 'hello\\n'; exit 3"
p [reader.class, writer.class, pid.class]
p reader.equal?(writer)
p reader.gets
Process.wait pid
p $?.exitstatus
p PTY.check(pid)

controlling, terminal = PTY.open
p [controlling.class, terminal.class]
p terminal.tty?, controlling.tty?
p terminal.path.start_with?("/dev/")
terminal.write "typed\n"
p controlling.readpartial(100)
controlling.write "back\n"
p terminal.gets
controlling.close
terminal.close
PTY.open { |pair| p pair.map(&:class) }
p PTY.open { :answer }

child = fork { sleep 5 }
p PTY.check(child)
Process.kill :KILL, child
status = nil
status = PTY.check(child) until status
p status.class, status.signaled?

PTY.spawn("echo", "block form") { |output, _input, spawned| p output.gets; Process.wait spawned }
greeting = PTY.spawn({ "GREETING" => "hi" }, "echo $GREETING")
p greeting[0].gets
Process.wait greeting[2]

ending = PTY.spawn("exit 7")[2]
begin
  loop { PTY.check ending, true }
rescue PTY::ChildExited => error
  p error.status.exitstatus
  p error.message == "pty - exited: #{ending}"
end

Output:

[:check, :getpty, :open, :spawn]
RuntimeError
[File, File, Integer]
false
"hello\r\n"
3
nil
[IO, File]
true
true
true
"typed\r\n"
"back\n"
[IO, File]
:answer
nil
Process::Status
true
"block form\r\n"
"hi\r\n"
7
true