threading for better synchronisation

wrapper.py

@@ -11,6 +11,7 @@ import re
 import signal
 import subprocess
 import tempfile
+import threading
 import time
 
 def parse_senders( sender_args, sender ):
@@ -116,6 +117,13 @@ def clean_up():
 #        i['utility_file'].close()
     time.sleep(1)
 
+def start_utility(single_sender, scheduled_time):
+    time.sleep(abs(scheduled_time - time.perf_counter()))
+    single_sender['utility'] = subprocess.Popen(single_sender['utility_command'],
+                                                stdout=single_sender['utility_file'])
+
+
+
 signal.signal(signal.SIGINT, signal_handler)
 signal.signal(signal.SIGTERM, signal_handler)
 
@@ -223,7 +231,17 @@ for key, i in enumerate(sender):
 start_time = time.perf_counter()
 
 for key, i in enumerate(sender):
-    i['utility'] = subprocess.Popen(i['utility_command'], stdout=i['utility_file'])
+#    i['utility'] = subprocess.Popen(i['utility_command'], stdout=i['utility_file'])
+
+    # try to run all senders at the same time through threading 5 seconds from now
+    scheduled_time = time.perf_counter() + 5
+#    StartUtilityThread(i, scheduled_time).start()
+    i['thread'] = threading.Thread(target=start_utility, args=(i, scheduled_time))
+    i['thread'].start()
+    
+#time.sleep(5)
+for key, i in enumerate(sender):
+    i['thread'].join()
     print(i['utility'].args)
 
 if args.utility != "netperf":