Flush out and err in exec cmd fct.

utils.py

@@ -36,6 +36,9 @@ def exec_cmd(cmd, log_output=True, get_output=True):
         out = out.strip()
         if log_output:
             log(out)
+    elif log_output:
+        sys.stdout.flush()
+        sys.stderr.flush()
     return p.returncode, out