diff --git a/doc/socat.yo b/doc/socat.yo
index d8f2ab0..4124a35 100644
--- a/doc/socat.yo
+++ b/doc/socat.yo
@@ -1981,9 +1981,9 @@ label(OPTION_SO_TYPE)dit(bf(tt(type=<type>)))
    [link(int)(TYPE_INT)]. Address resolution is not affected by this option.
    Under Linux, 1 means stream oriented socket, 2 means datagram socket, and 3
    means raw socket.
-label(OPTION_SO_PROTOTYPE)dit(bf(tt(prototype)))
+label(OPTION_SO_PROTOCOL)dit(bf(tt(protocol)))
    Sets the protocol of the socket, specified as third argument to the
-   code(socket()) or code(socketpair()) calls, to <prototype>
+   code(socket()) or code(socketpair()) calls, to <protocol>
    [link(int)(TYPE_INT)]. Address resolution is not affected by this option.
    6 means TCP, 17 means UDP.
 COMMENT(label(OPTION_USELOOPBACK)dit(bf(tt(useloopback)))
diff --git a/xio-socket.c b/xio-socket.c
index 3508254..7f4e461 100644
--- a/xio-socket.c
+++ b/xio-socket.c
@@ -173,7 +173,7 @@ const struct optdesc opt_so_dontlinger = {"so-dontlinger", "dontlinger",  OPT_SO
 #endif
 /* the SO_PROTOTYPE is OS defined on Solaris, HP-UX; we lend this for a more
    general purpose */
-const struct optdesc opt_so_prototype  = {"so-prototype",  "prototype",   OPT_SO_PROTOTYPE,   GROUP_SOCKET,PH_SOCKET,    TYPE_INT,OFUNC_SPEC,   SOL_SOCKET,SO_PROTOTYPE };
+const struct optdesc opt_so_prototype  = {"so-protocol",  "protocol",   OPT_SO_PROTOTYPE,   GROUP_SOCKET,PH_SOCKET,    TYPE_INT,OFUNC_SPEC,   SOL_SOCKET,SO_PROTOCOL };
 #ifdef FIOSETOWN
 const struct optdesc opt_fiosetown   = { "fiosetown", NULL, OPT_FIOSETOWN,   GROUP_SOCKET, PH_PASTSOCKET, TYPE_INT,  OFUNC_IOCTL,  FIOSETOWN };
 #endif
diff --git a/xio-socket.h b/xio-socket.h
index e8f123c..62cfe72 100644
--- a/xio-socket.h
+++ b/xio-socket.h
@@ -5,10 +5,18 @@
 #ifndef __xio_socket_h_included
 #define __xio_socket_h_included 1
 
-/* SO_PROTOTYPE is OS defined on Solaris, HP-UX; we lend this for a more
-   general purpose */ 
-#ifndef SO_PROTOTYPE
-#define SO_PROTOTYPE 0x9999
+/* SO_PROTOTYPE is defined on Solaris, HP-UX
+   SO_PROTOCOL in Linux, is the better name, but came much later */
+#ifdef SO_PROTOCOL
+#  undef SO_PROTOTYPE
+#    define SO_PROTOTYPE SO_PROTOCOL
+#else
+#  ifdef SO_PROTOTYPE
+#    define SO_PROTOCOL SO_PROTOTYPE
+#  else
+#    define SO_PROTOCOL 0x9999
+#    define SO_PROTOTYPE SO_PROTOCOL
+#  endif
 #endif
 
 extern const struct addrdesc xioaddr_socket_connect;
diff --git a/xioopts.c b/xioopts.c
index ba2062b..6854235 100644
--- a/xioopts.c
+++ b/xioopts.c
@@ -1519,6 +1519,7 @@ const struct optname optionnames[] = {
 	IF_SOCKET ("so-priority",	&opt_so_priority)
 #endif
 #ifdef SO_PROTOTYPE
+	IF_SOCKET ("so-protocol",	&opt_so_prototype)
 	IF_SOCKET ("so-prototype",	&opt_so_prototype)
 #endif
 	IF_SOCKET ("so-rcvbuf",	&opt_so_rcvbuf)