Make the exit status consistent across all programs

(except nfdc)

Change-Id: Ia3edb11b3f4284df5db8279b06e6fb708ae454e9
diff --git a/docs/manpages/nfd-autoreg.rst b/docs/manpages/nfd-autoreg.rst
index d2fb303..33e94bd 100644
--- a/docs/manpages/nfd-autoreg.rst
+++ b/docs/manpages/nfd-autoreg.rst
@@ -1,4 +1,4 @@
-ndn-autoreg
+nfd-autoreg
 ===========
 
 Usage
@@ -11,23 +11,20 @@
 Description
 -----------
 
-``autoreg-server`` is a daemon application that automatically registers the specified
-prefix(es) when new on-demand Faces are created (i.e., when a new UDP face is created as
+``nfd-autoreg`` is a daemon application that automatically registers the specified
+prefix(es) when new on-demand faces are created (i.e., when a new UDP face is created as
 the result of an incoming packet or when a new TCP face is created as the result of an
 incoming connection).
 
 Options
 -------
 
-``-h`` or ``--help``
-  Produce help message.
-
 ``-i`` or ``--prefix``
   Prefix that should be automatically registered when a new remote face is created.
-  Can be repeated multiple to specify additional prefixes.
+  Can be repeated multiple times to specify additional prefixes.
 
 ``-c`` or ``--cost``
-  RIB cost to be assigned to auto-registered prefixes.   if not specified, default cost
+  RIB cost to be assigned to auto-registered prefixes.   If not specified, default cost
   is set to 255.
 
 ``-w`` or ``--whitelist``
@@ -48,10 +45,27 @@
 
   Default: none
 
+``-h`` or ``--help``
+  Print help message and exit.
+
+``-V`` or ``--version``
+  Show version information and exit.
+
+Exit status
+-----------
+
+0: No error.
+
+1: An unspecified error occurred.
+
+2: Malformed command line, e.g., invalid, missing, or unknown argument.
+
+4: Insufficient privileges.
+
 Examples
 --------
 
-Auto-register two prefixes for any newly created on-demand Face, except those that has
+Auto-register two prefixes for any newly created on-demand face, except those that has
 source IP address in ``10.0.0.0/8`` network::
 
     nfd-autoreg --prefix=/app1/video --prefix=/app2/pictures -b 10.0.0.0/8