From 14f214e31c720c833b77867a718a2770adf659c8 Mon Sep 17 00:00:00 2001
From: Keenan Brock <keenan@thebrocks.net>
Date: Mon, 15 Jun 2015 10:35:00 -0400
Subject: [PATCH] Introduce detach

this spawns a thread but runs in a separate
process.

It can run in the same or a different
---
 lib/awesome_spawn.rb | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/lib/awesome_spawn.rb b/lib/awesome_spawn.rb
index 3ee2326..df7a665 100644
--- a/lib/awesome_spawn.rb
+++ b/lib/awesome_spawn.rb
@@ -114,6 +114,35 @@ def run!(command, options = {})
     command_result
   end
 
+  # Execute `command` in a detached manner
+  # The defalt is to spawn a new child process that sends the output to the null device
+  # @param [String] command the command to execute
+  # @param [Hash{Symbol,Object}] options the Kernel.spawn options
+  #   by default the :err, and :out are redirected to the null device.
+  #   For windows, default :pgroup_new is true (make a root process of a new process group)
+  #   For others,  default :pgroup is true (make a new process group)
+  # @returns [Integer] pid of new process
+  #
+  # @example With normal output
+  #   AwesomeSpawn.run_detached('echo "Hi" > /tmp/out')
+  #   # => 79901
+  #
+  # if a user defines :out or :err, it is assumed they will define both
+  def run_detached(command, options = {})
+    env, command_line, options = parse_command_options(command, options)
+    # maybe add support later for this
+    raise ArgumentError, "options cannot contain :in_data" if options.include?(:in_data)
+
+    options[[:out, :err]] = [IO::NULL, "w"] unless (options.keys.flatten & [:out, :err]).any?
+    if Gem.win_platform?
+      options[:new_pgroup]  = true unless options.key?(:new_pgroup)
+    else
+      options[:pgroup]      = true unless options.key?(:pgroup)
+    end
+
+    detach(env, command_line, options)
+  end
+
   # (see CommandLineBuilder#build)
   def build_command_line(command, params = nil)
     CommandLineBuilder.new.build(command, params)
@@ -139,4 +168,8 @@ def parse_command_options(command, options)
 
     [env, build_command_line(command, params), options]
   end
+
+  def detach(env, command, options)
+    Process.detach(Kernel.spawn(env, command, options)).pid
+  end
 end