Ruby processes
From wikinotes
Documentation
Process docs https://docs.ruby-lang.org/en/2.7.0/Process.html
Subprocesses
Process functions create/operate on a PID (instead of an object representing the process, like python).
Backticks
`ls -la | grep foo` puts "exit code is 0" if $?.successSpawn
pid = Process.spawn(['ls', '-la']) puts pid # 123456 Process.wait pidManipulating STDIN, STDOUT, STDERR.
# STDIN from file Process.spawn("/usr/bin/cat", in: File.open("/home/you/.zshrc", "r")) # STDIN from string r_pipe, w_pipe = IO.pipe w_pipe.write("a\nb\nc") w_pipe.close Process.spawn("/usr/bin/cat", in: r_pipe) r_pipe.closeYou can also wrap everything
in_r, in_w = IO.pipe out_r, out_w = IO.pipe err_r, err_w = IO.pipe pid = Process.spawn("netstat", "-an", in: in_r, out: out_w, err: err_w) communicator = OpenStruct.new(pid: pid, in: in_w, out: out_r, err: err_r)
Fork
Fork allows you to run ruby code in a separate process.
pid = Process.fork do puts "child, pid #{Process.pid} sleeping..." sleep 5 puts "child exiting" end Process.wait pid