improve commandline argument behaviour

+ allow hprt2 / zebra2

base.py

@@ -138,7 +138,7 @@ class ServiceManager:
         for ins in parser.sections():
             section = dict(parser[ins])
             if ins == 'MAIN':
-                ins = self.main_ins = basename(expanduser('~'))
+                ins = self.main_ins = os.environ.get('Instrument') or basename(expanduser('~'))
             if 'REMOTE_HOST' in section:
                 self.remote_hosts[ins] = section['REMOTE_HOST']
             command = section.get('%s_command' % self.group)
@@ -470,7 +470,8 @@ class ServiceManager:
 
     def do_help(self, *args):
         if self.main_ins:
-            usage = self.USAGE.replace(' <instance>', '').replace(' [<instance>]', '') % ''
+            usage = self.USAGE.replace('<instance>', '[instance]') % (
+               '[instance] is empty or one of %s' % ', '.join(self.info))
         else:
             usage = self.USAGE % ('<instance> is one of %s' % ', '.join(self.info))
         print(usage)
@@ -479,7 +480,7 @@ class ServiceManager:
         if unknown:
             raise UsageError('unknown argument: %s' % (' '.join(unknown)))
         if extra:
-            return [argdict.get('ins'), argdict.get('service')] + extra
+            return [argdict.get('ins'), argdict.get('service')] + list(extra)
         args = [argdict.get('ins'), argdict.get('service')]
         while args and not args[-1]:
             args.pop()