Daemon handling cleanup.

More cleanly handling whether a PID file should be checked.
Fatal Error on PID file IOError.
Pylint fix to bootstrap.

homeassistant/__main__.py

@@ -118,7 +118,6 @@ def daemonize():
 def check_pid(pid_file):
     """ Check that HA is not already running """
     # check pid file
-    if pid_file:
     try:
         pid = int(open(pid_file, 'r').readline())
     except IOError:
@@ -142,7 +141,8 @@ def write_pid(pid_file):
         try:
             open(pid_file, 'w').write(str(pid))
         except IOError:
-            pass
+            print('Fatal Error: Unable to write pid file {}'.format(pid_file))
+            sys.exit(1)
 
 
 def main():
@@ -155,6 +155,7 @@ def main():
     ensure_config_path(config_dir)
 
     # daemon functions
+    if args.pid_file:
         check_pid(args.pid_file)
     if args.daemon:
         daemonize()

homeassistant/bootstrap.py

@@ -149,7 +149,7 @@ def mount_local_lib_path(config_dir):
     sys.path.insert(0, os.path.join(config_dir, 'lib'))
 
 
-# pylint: disable=too-many-branches, too-many-statements
+# pylint: disable=too-many-branches, too-many-statements, too-many-arguments
 def from_config_dict(config, hass=None, config_dir=None, enable_log=True,
                      verbose=False, daemon=False):
     """