fix(docs): fixup based on changes in master

Docker-DCO-1.1-Signed-off-by: Brandon Philips <brandon.philips@coreos.com> (github: philips)

docker/docker.go

@@ -43,7 +43,7 @@ func main() {
 		flMtu                = flag.Int([]string{"#mtu", "-mtu"}, docker.DefaultNetworkMtu, "Set the containers network mtu")
 	)
 	flag.Var(&flDns, []string{"#dns", "-dns"}, "Force docker to use specific DNS servers")
-	flag.Var(&flHosts, []string{"H", "-host"}, "Multiple tcp://host:port or unix://path/to/socket to bind in daemon mode, single connection otherwise")
+	flag.Var(&flHosts, []string{"H", "-host"}, "tcp://host:port, unix://path/to/socket, fd://* or fd://socketfd to use in daemon mode. Multiple sockets can be specified")
 
 	flag.Parse()
 

docs/sources/reference/commandline/cli.rst

@@ -27,7 +27,7 @@ To list available commands, either run ``docker`` with no parameters or execute
 
     Usage of docker:
       -D, --debug=false: Enable debug mode
-      -H, --host=[]: Multiple tcp://host:port or unix://path/to/socket to bind in daemon mode, single connection otherwise
+      -H, --host=[]: Multiple tcp://host:port or unix://path/to/socket to bind in daemon mode, single connection otherwise. systemd socket activation can be used with fd://[socketfd].
       --api-enable-cors=false: Enable CORS headers in the remote API
       -b, --bridge="": Attach containers to a pre-existing network bridge; use 'none' to disable container networking
       --bip="": Use this CIDR notation address for the network bridge's IP, not compatible with -b
@@ -63,6 +63,8 @@ the ``-H`` flag for the client.
         # both are equal
 
 
+To run the daemon with socket activation, use ``docker -d -H fd://*``. Individual sockets can also be specified ``docker -d -H fd://3``.
+
 .. _cli_attach:
 
 ``attach``