Use Process.spawn to start gui and server

src/cmd/cmdsim.rb.in

@@ -28,6 +28,7 @@ end
 require 'optparse'
 require 'erb'
 require 'pathname'
+require 'rbconfig'
 
 # Constants.
 LIBRARY_NAME = '@library_location@'
@@ -379,9 +380,42 @@ class Cmd
  options
  end # parse()
 
+ def run_server_and_gui(args)
+ # Start server process
+ serverPid = Process.spawn('gz', *args, '-s')
+
+ # Start GUI process
+ guiPid = Process.spawn('gz', *args, '-g')
+
+ Signal.trap("INT") {
+ # Use a method to kill processes, passing PID and timeout
+ killProcess(guiPid, "Gazebo Sim GUI", 5.0)
+ killProcess(serverPid, "Gazebo Sim Server", 5.0)
+ exit(1)
+ }
+
+ # Wait for a child process to end
+ pid, status = Process.wait2
+
+ if pid == serverPid
+ self.killProcess(guiPid, "Gazebo Sim GUI", 5.0)
+ else
+ self.killProcess(serverPid, "Gazebo Sim Server", 5.0)
+ end
+
+ exit(0)
+ end # run_server_and_gui()
+
  def execute(args)
+ orig_args = args.dup
  options = parse(args)
 
+ # Neither the -s nor -g options were used, so re-run with both the server
+ # and gui.
+ if options['server'] == 0 && options['gui'] == 0
+ return run_server_and_gui(orig_args)
+ end
+
  library_name_path = Pathname.new(LIBRARY_NAME)
  if library_name_path.absolute?
  # If the first character is a slash, we'll assume that we've been given an
@@ -516,71 +550,8 @@ Please use [GZ_SIM_RESOURCE_PATH] instead."
  options['gui_config'] = "_playback_"
  end
 
- # Neither the -s nor -g options were used, so run both the server
- # and gui.
- if options['server'] == 0 && options['gui'] == 0
-
- if plugin.end_with? ".dylib"
- puts "On macOS `gz sim` currently only works with either the -s argument
-or the -g argument, you cannot run both server and gui in one terminal.
-See https://github.com/gazebosim/gz-sim/issues/44 for more info."
- exit(-1)
- end
-
- if plugin.end_with? ".dll"
- puts "`ign gazebo` currently only works with the -s argument on Windows.
-See https://github.com/gazebosim/gz-sim/issues/168 for more info."
- exit(-1)
- end
-
- serverPid = Process.fork do
- ENV['RMT_PORT'] = '1500'
- Process.setpgid(0, 0)
- Process.setproctitle('gz sim server')
- Importer.runServer(parsed,
- options['iterations'], options['run'], options['hz'],
- options['initial_sim_time'], options['levels'],
- options['network_role'], options['network_secondaries'],
- options['record'], options['record-path'],
- options['record-resources'], options['log-overwrite'],
- options['log-compress'], options['playback'],
- options['physics_engine'],
- options['render_engine_server'],
- options['render_engine_server_api_backend'],
- options['render_engine_gui'],
- options['render_engine_gui_api_backend'],
- options['file'], options['record-topics'].join(':'),
- options['wait_gui'],
- options['headless-rendering'], options['record-period'],
- options['seed'])
- end
-
- guiPid = Process.fork do
- ENV['RMT_PORT'] = '1501'
- Process.setpgid(0, 0)
- Process.setproctitle('gz sim gui')
- Importer.runGui(options['gui_config'], options['file'],
- options['wait_gui'], options['render_engine_gui'],
- options['render_engine_gui_api_backend'])
- end
-
- Signal.trap("INT") {
- self.killProcess(guiPid, "Gazebo Sim GUI", 5.0)
- self.killProcess(serverPid, "Gazebo Sim Server", 5.0)
- return 1
- }
-
- # Wait for a child process to end
- pid, status = Process.wait2
-
- if pid == serverPid
- self.killProcess(guiPid, "Gazebo Sim GUI", 5.0)
- else
- self.killProcess(serverPid, "Gazebo Sim Server", 5.0)
- end
-
  # If the -s option was specified, then run only the server
- elsif options['server'] == 1
+ if options['server'] == 1
  ENV['RMT_PORT'] = '1500'
  Importer.runServer(parsed, options['iterations'], options['run'],
  options['hz'], options['initial_sim_time'], options['levels'],