diff --git a/include/rpc/auth.h b/include/rpc/auth.h
index bf0d76c046c6..8773e7115d12 100644
--- a/include/rpc/auth.h
+++ b/include/rpc/auth.h
@@ -279,11 +279,12 @@ __END_DECLS
  * Netname manipulation routines.
  */
 __BEGIN_DECLS
-extern int getnetname(char *);
-extern int host2netname(char *, const char *, const char *);
-extern int user2netname(char *, const uid_t, const char *);
-extern int netname2user(char *, uid_t *, gid_t *, int *, gid_t *);
-extern int netname2host(char *, char *, const int);
+extern int getnetname(char [MAXNETNAMELEN + 1]);
+extern int host2netname(char [MAXNETNAMELEN + 1], const char *, const char *);
+extern int user2netname(char [MAXNETNAMELEN + 1], const uid_t, const char *);
+extern int netname2user(char [MAXNETNAMELEN + 1], uid_t *, gid_t *, int *,
+    gid_t *);
+extern int netname2host(char [MAXNETNAMELEN + 1], char *, const int);
 extern void passwd2des ( char *, char * );
 __END_DECLS
 
diff --git a/lib/libc/rpc/netnamer.c b/lib/libc/rpc/netnamer.c
index 591f6d5c91e5..8062c446dffe 100644
--- a/lib/libc/rpc/netnamer.c
+++ b/lib/libc/rpc/netnamer.c
@@ -64,7 +64,7 @@ static char    *NETID = "netid.byname";
 static char    *NETIDFILE = "/etc/netid";
 
 static int getnetid( char *, char * );
-static int _getgroups( char *, gid_t * );
+static int _getgroups( char *, gid_t [NGRPS] );
 
 /*
  * Convert network-name into unix credential