allow the config file location to be specified in $SUPERVISOR_CONFIG

docs/configuration.rst

@@ -3,12 +3,13 @@ Configuration File
 
 The Supervisor configuration file is conventionally named
 :file:`supervisord.conf`.  It is used by both :program:`supervisord`
-and :program:`supervisorctl`.  If either application is started
-without the ``-c`` option (the option which is used to tell the
-application the configuration filename explicitly), the application
-will look for a file named :file:`supervisord.conf` within the
-following locations, in the specified order.  It will use the first
-file it finds.
+and :program:`supervisorctl`. Either application can be starting with
+the ``-c`` or ``--configuration`` option, which is used to tell the
+application the configuration filename explicitly. Alternatively the
+config file can be specified in the ``$SUPERVISOR_CONFIG`` environment
+variable. If neither is he application will look for a file named
+:file:`supervisord.conf` within the following locations, in the
+specified order.  It will use the first file it finds.
 
 #. :file:`$CWD/supervisord.conf`
 

supervisor/options.py

@@ -101,7 +101,7 @@ def __init__(self, require_configfile=True):
         self.attr_priorities = {}
         self.require_configfile = require_configfile
         self.add(None, None, "h", "help", self.help)
-        self.add("configfile", None, "c:", "configuration=")
+        self.add("configfile", None, "c:", "configuration=", env="SUPERVISOR_CONFIG")
 
         here = os.path.dirname(os.path.dirname(sys.argv[0]))
         searchpaths = [os.path.join(here, 'etc', 'supervisord.conf'),