IPC option rework (pipe/conn) to reduce code duplication.

9 files changed, 151 insertions, 95 deletions

diff --git a/src/core/defs.h b/src/core/defs.h
index 5c06cf53..32d6782a 100644
--- a/src/core/defs.h
+++ b/src/core/defs.h
@@ -139,7 +139,7 @@ typedef struct {
 
 // Types.  These are used to provide more structured access to options
 // (and maybe later statistics).  For now these are internal only.
-typedef enum nni_opt_type {
+typedef enum {
 	NNI_TYPE_OPAQUE,
 	NNI_TYPE_BOOL,
 	NNI_TYPE_INT32,
@@ -151,6 +151,8 @@ typedef enum nni_opt_type {
 	NNI_TYPE_STRING,
 	NNI_TYPE_SOCKADDR,
 	NNI_TYPE_POINTER,
-} nni_opt_type;
+} nni_type;
+
+typedef nni_type nni_opt_type;
 
 #endif // CORE_DEFS_H
diff --git a/src/core/listener.c b/src/core/listener.c
index 84f8cafd..83f6ca41 100644
--- a/src/core/listener.c
+++ b/src/core/listener.c
@@ -370,6 +370,13 @@ nni_listener_setopt(nni_listener *l, const char *name, const void *val,
 		return (NNG_EREADONLY);
 	}
 
+	if (l->l_ops.l_setopt != NULL) {
+		int rv = l->l_ops.l_setopt(l->l_data, name, val, sz, t);
+		if (rv != NNG_ENOTSUP) {
+			return (rv);
+		}
+	}
+
 	for (o = l->l_ops.l_options; o && o->o_name; o++) {
 		if (strcmp(o->o_name, name) != 0) {
 			continue;
@@ -390,6 +397,13 @@ nni_listener_getopt(
 {
 	nni_option *o;
 
+	if (l->l_ops.l_getopt != NULL) {
+		int rv = l->l_ops.l_getopt(l->l_data, name, valp, szp, t);
+		if (rv != NNG_ENOTSUP) {
+			return (rv);
+		}
+	}
+
 	for (o = l->l_ops.l_options; o && o->o_name; o++) {
 		if (strcmp(o->o_name, name) != 0) {
 			continue;
diff --git a/src/core/options.c b/src/core/options.c
index d61b35ac..097b92b2 100644
--- a/src/core/options.c
+++ b/src/core/options.c
@@ -366,3 +366,35 @@ nni_copyout_str(const char *str, void *dst, size_t *szp, nni_opt_type t)
 		return (NNG_EBADTYPE);
 	}
 }
+
+int
+nni_getopt(const nni_option *opts, const char *nm, void *arg, void *buf,
+    size_t *szp, nni_opt_type otype)
+{
+	while (opts->o_name != NULL) {
+		if (strcmp(opts->o_name, nm) == 0) {
+			if (opts->o_get == NULL) {
+				return (NNG_EWRITEONLY);
+			}
+			return (opts->o_get(arg, buf, szp, otype));
+		}
+		opts++;
+	}
+	return (NNG_ENOTSUP);
+}
+
+int
+nni_setopt(const nni_option *opts, const char *nm, void *arg, const void *buf,
+    size_t sz, nni_opt_type otype)
+{
+	while (opts->o_name != NULL) {
+		if (strcmp(opts->o_name, nm) == 0) {
+			if (opts->o_set == NULL) {
+				return (NNG_EREADONLY);
+			}
+			return (opts->o_set(arg, buf, sz, otype));
+		}
+		opts++;
+	}
+	return (NNG_ENOTSUP);
+}
\ No newline at end of file
diff --git a/src/core/options.h b/src/core/options.h
index f0ab9811..c0d5b23d 100644
--- a/src/core/options.h
+++ b/src/core/options.h
@@ -24,32 +24,31 @@
 // in their own option handling, centralizing the logic for dealing with
 // variable sized options.
 
-extern int nni_copyin_ms(nni_duration *, const void *, size_t, nni_opt_type);
-extern int nni_copyin_bool(bool *, const void *, size_t, nni_opt_type);
-extern int nni_copyin_int(int *, const void *, size_t, int, int, nni_opt_type);
+extern int nni_copyin_ms(nni_duration *, const void *, size_t, nni_type);
+extern int nni_copyin_bool(bool *, const void *, size_t, nni_type);
+extern int nni_copyin_int(int *, const void *, size_t, int, int, nni_type);
 extern int nni_copyin_size(
-    size_t *, const void *, size_t, size_t, size_t, nni_opt_type);
-extern int nni_copyin_str(char *, const void *, size_t, size_t, nni_opt_type);
-extern int nni_copyin_ptr(void **, const void *, size_t, nni_opt_type);
-extern int nni_copyin_u64(uint64_t *, const void *, size_t, nni_opt_type);
-extern int nni_copyin_sockaddr(
-    nng_sockaddr *, const void *, size_t, nni_opt_type);
+    size_t *, const void *, size_t, size_t, size_t, nni_type);
+extern int nni_copyin_str(char *, const void *, size_t, size_t, nni_type);
+extern int nni_copyin_ptr(void **, const void *, size_t, nni_type);
+extern int nni_copyin_u64(uint64_t *, const void *, size_t, nni_type);
+extern int nni_copyin_sockaddr(nng_sockaddr *, const void *, size_t, nni_type);
 
 // nni_copyout_xxx copies out a type of the named value.  It assumes that
 // the type is aligned and the size correct, unless NNI_TYPE_OPAQUE is passed.
 extern int nni_copyout(const void *, size_t, void *, size_t *);
-extern int nni_copyout_bool(bool, void *, size_t *, nni_opt_type);
-extern int nni_copyout_int(int, void *, size_t *, nni_opt_type);
-extern int nni_copyout_ms(nng_duration, void *, size_t *, nni_opt_type);
-extern int nni_copyout_ptr(void *, void *, size_t *, nni_opt_type);
-extern int nni_copyout_size(size_t, void *, size_t *, nni_opt_type);
+extern int nni_copyout_bool(bool, void *, size_t *, nni_type);
+extern int nni_copyout_int(int, void *, size_t *, nni_type);
+extern int nni_copyout_ms(nng_duration, void *, size_t *, nni_type);
+extern int nni_copyout_ptr(void *, void *, size_t *, nni_type);
+extern int nni_copyout_size(size_t, void *, size_t *, nni_type);
 extern int nni_copyout_sockaddr(
-    const nng_sockaddr *, void *, size_t *, nni_opt_type);
-extern int nni_copyout_u64(uint64_t, void *, size_t *, nni_opt_type);
+    const nng_sockaddr *, void *, size_t *, nni_type);
+extern int nni_copyout_u64(uint64_t, void *, size_t *, nni_type);
 
 // nni_copyout_str copies out a string.  If the type is NNI_TYPE_STRING,
 // then it passes through a pointer, created by nni_strdup().
-extern int nni_copyout_str(const char *, void *, size_t *, nni_opt_type);
+extern int nni_copyout_str(const char *, void *, size_t *, nni_type);
 
 // nni_option is used for socket, protocol, transport, and similar options.
 // Note that only for transports, the o_set member may be called with a NULL
@@ -65,13 +64,20 @@ struct nni_option_s {
 	// the actual size of the object that would have been copied
 	// is supplied by the function in the size.  If the object did
 	// not fit, then NNG_EINVAL is returned.
-	int (*o_get)(void *, void *, size_t *, nni_opt_type);
+	int (*o_get)(void *, void *, size_t *, nni_type);
 
 	// o_set is used to set the value of the option.  For transport
 	// endpoints only, the instance parameter (first argument) may be
 	// NULL, in which case only a generic validation of the parameters
 	// is performed.  (This is used when setting socket options before
-	int (*o_set)(void *, const void *, size_t, nni_opt_type);
+	int (*o_set)(void *, const void *, size_t, nni_type);
 };
 
+// nni_getopt and nni_setopt are helper functions to implement options
+// based on arrays of nni_option structures.
+extern int nni_getopt(
+    const nni_option *, const char *, void *, void *, size_t *, nni_type);
+extern int nni_setopt(
+    const nni_option *, const char *, void *, const void *, size_t, nni_type);
+
 #endif // CORE_OPTIONS_H
diff --git a/src/core/pipe.c b/src/core/pipe.c
index 9357cee4..664dd3c2 100644
--- a/src/core/pipe.c
+++ b/src/core/pipe.c
@@ -291,6 +291,13 @@ nni_pipe_getopt(
 {
 	nni_option *o;
 
+	if (p->p_tran_ops.p_getopt != NULL) {
+		int rv;
+		rv = p->p_tran_ops.p_getopt(p->p_tran_data, name, val, szp, t);
+		if (rv != NNG_ENOTSUP) {
+			return (rv);
+		}
+	}
 	for (o = p->p_tran_ops.p_options; o && o->o_name; o++) {
 		if (strcmp(o->o_name, name) != 0) {
 			continue;
diff --git a/src/core/platform.h b/src/core/platform.h
index 2b7eb9f1..a512c39f 100644
--- a/src/core/platform.h
+++ b/src/core/platform.h
@@ -379,16 +379,15 @@ extern int nni_ipc_conn_get_peer_zoneid(nni_ipc_conn *, uint64_t *);
 // nni_ipc_conn_setopt is like setsockopt, but uses string names. These
 // are the same names from the IPC transport, generally.  There are no
 // options that are generally settable on an IPC connection.
-// NNG_OPT_REMADDR, NNG_OPT_LOCADDR, NNG_OPT_IPC_PERMISSIONS,
-// NNG_OPT_
 extern int nni_ipc_conn_setopt(
-    nni_ipc_conn *, const char *, const void *, size_t);
+    nni_ipc_conn *, const char *, const void *, size_t, nni_opt_type);
 
 // nni_ipc_conn_getopt is like getsockopt, but uses string names.
 // We support NNG_OPT_REMADDR and NNG_OPT_LOCADDR (with argument type
 // nng_sockaddr), and on some platforms NNG_OPT_IPC_PEER_[UID,GID,ZONEID]
 // (with type uint64_t.)
-extern int nni_ipc_conn_getopt(nni_ipc_conn *, const char *, void *, size_t *);
+extern int nni_ipc_conn_getopt(
+    nni_ipc_conn *, const char *, void *, size_t *, nni_opt_type);
 
 // nni_ipc_dialer_init creates a new dialer object.
 extern int nni_ipc_dialer_init(nni_ipc_dialer **);
diff --git a/src/core/socket.c b/src/core/socket.c
index 888200ef..387796a6 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -36,7 +36,7 @@ struct nni_ctx {
 typedef struct nni_sockopt {
 	nni_list_node node;
 	char *        name;
-	nni_opt_type  typ;
+	nni_type      typ;
 	size_t        sz;
 	void *        data;
 } nni_sockopt;
@@ -145,7 +145,7 @@ sock_get_fd(void *s, int flag, int *fdp)
 }
 
 static int
-sock_get_sendfd(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_sendfd(void *s, void *buf, size_t *szp, nni_type t)
 {
 	int fd;
 	int rv;
@@ -157,7 +157,7 @@ sock_get_sendfd(void *s, void *buf, size_t *szp, nni_opt_type t)
 }
 
 static int
-sock_get_recvfd(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_recvfd(void *s, void *buf, size_t *szp, nni_type t)
 {
 	int fd;
 	int rv;
@@ -169,38 +169,38 @@ sock_get_recvfd(void *s, void *buf, size_t *szp, nni_opt_type t)
 }
 
 static int
-sock_get_raw(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_raw(void *s, void *buf, size_t *szp, nni_type t)
 {
 	bool raw = ((nni_sock_flags(SOCK(s)) & NNI_PROTO_FLAG_RAW) != 0);
 	return (nni_copyout_bool(raw, buf, szp, t));
 }
 
 static int
-sock_set_recvtimeo(void *s, const void *buf, size_t sz, nni_opt_type t)
+sock_set_recvtimeo(void *s, const void *buf, size_t sz, nni_type t)
 {
 	return (nni_copyin_ms(&SOCK(s)->s_rcvtimeo, buf, sz, t));
 }
 
 static int
-sock_get_recvtimeo(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_recvtimeo(void *s, void *buf, size_t *szp, nni_type t)
 {
 	return (nni_copyout_ms(SOCK(s)->s_rcvtimeo, buf, szp, t));
 }
 
 static int
-sock_set_sendtimeo(void *s, const void *buf, size_t sz, nni_opt_type t)
+sock_set_sendtimeo(void *s, const void *buf, size_t sz, nni_type t)
 {
 	return (nni_copyin_ms(&SOCK(s)->s_sndtimeo, buf, sz, t));
 }
 
 static int
-sock_get_sendtimeo(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_sendtimeo(void *s, void *buf, size_t *szp, nni_type t)
 {
 	return (nni_copyout_ms(SOCK(s)->s_sndtimeo, buf, szp, t));
 }
 
 static int
-sock_set_recvbuf(void *s, const void *buf, size_t sz, nni_opt_type t)
+sock_set_recvbuf(void *s, const void *buf, size_t sz, nni_type t)
 {
 	int len;
 	int rv;
@@ -212,7 +212,7 @@ sock_set_recvbuf(void *s, const void *buf, size_t sz, nni_opt_type t)
 }
 
 static int
-sock_get_recvbuf(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_recvbuf(void *s, void *buf, size_t *szp, nni_type t)
 {
 	int len = nni_msgq_cap(SOCK(s)->s_urq);
 
@@ -220,7 +220,7 @@ sock_get_recvbuf(void *s, void *buf, size_t *szp, nni_opt_type t)
 }
 
 static int
-sock_set_sendbuf(void *s, const void *buf, size_t sz, nni_opt_type t)
+sock_set_sendbuf(void *s, const void *buf, size_t sz, nni_type t)
 {
 	int len;
 	int rv;
@@ -232,7 +232,7 @@ sock_set_sendbuf(void *s, const void *buf, size_t sz, nni_opt_type t)
 }
 
 static int
-sock_get_sendbuf(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_sendbuf(void *s, void *buf, size_t *szp, nni_type t)
 {
 	int len = nni_msgq_cap(SOCK(s)->s_uwq);
 
@@ -240,38 +240,38 @@ sock_get_sendbuf(void *s, void *buf, size_t *szp, nni_opt_type t)
 }
 
 static int
-sock_get_sockname(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_sockname(void *s, void *buf, size_t *szp, nni_type t)
 {
 	return (nni_copyout_str(SOCK(s)->s_name, buf, szp, t));
 }
 
 static int
-sock_set_sockname(void *s, const void *buf, size_t sz, nni_opt_type t)
+sock_set_sockname(void *s, const void *buf, size_t sz, nni_type t)
 {
 	return (nni_copyin_str(
 	    SOCK(s)->s_name, buf, sizeof(SOCK(s)->s_name), sz, t));
 }
 
 static int
-sock_get_proto(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_proto(void *s, void *buf, size_t *szp, nni_type t)
 {
 	return (nni_copyout_int(nni_sock_proto_id(SOCK(s)), buf, szp, t));
 }
 
 static int
-sock_get_peer(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_peer(void *s, void *buf, size_t *szp, nni_type t)
 {
 	return (nni_copyout_int(nni_sock_peer_id(SOCK(s)), buf, szp, t));
 }
 
 static int
-sock_get_protoname(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_protoname(void *s, void *buf, size_t *szp, nni_type t)
 {
 	return (nni_copyout_str(nni_sock_proto_name(SOCK(s)), buf, szp, t));
 }
 
 static int
-sock_get_peername(void *s, void *buf, size_t *szp, nni_opt_type t)
+sock_get_peername(void *s, void *buf, size_t *szp, nni_type t)
 {
 	return (nni_copyout_str(nni_sock_peer_name(SOCK(s)), buf, szp, t));
 }
@@ -957,14 +957,13 @@ nni_sock_add_dialer(nni_sock *s, nni_dialer *d)
 
 int
 nni_sock_setopt(
-    nni_sock *s, const char *name, const void *v, size_t sz, nni_opt_type t)
+    nni_sock *s, const char *name, const void *v, size_t sz, nni_type t)
 {
-	int               rv = NNG_ENOTSUP;
-	nni_dialer *      d;
-	nni_listener *    l;
-	nni_sockopt *     optv;
-	nni_sockopt *     oldv = NULL;
-	const nni_option *opt;
+	int           rv;
+	nni_dialer *  d;
+	nni_listener *l;
+	nni_sockopt * optv;
+	nni_sockopt * oldv = NULL;
 
 	nni_mtx_lock(&s->s_mx);
 	if (s->s_closing) {
@@ -975,33 +974,18 @@ nni_sock_setopt(
 	// Protocol options.  The protocol can override options that
 	// the socket framework would otherwise supply, like buffer
 	// sizes.
-	for (opt = s->s_sock_ops.sock_options; opt->o_name != NULL; opt++) {
-		if (strcmp(opt->o_name, name) != 0) {
-			continue;
-		}
-		if (opt->o_set == NULL) {
-			nni_mtx_unlock(&s->s_mx);
-			return (NNG_EREADONLY);
-		}
-		rv = opt->o_set(s->s_data, v, sz, t);
+	rv = nni_setopt(s->s_sock_ops.sock_options, name, s->s_data, v, sz, t);
+	if (rv != NNG_ENOTSUP) {
 		nni_mtx_unlock(&s->s_mx);
 		return (rv);
 	}
 
 	// Some options do not go down to transports.  Handle them directly.
-	for (opt = sock_options; opt->o_name != NULL; opt++) {
-		if (strcmp(opt->o_name, name) != 0) {
-			continue;
-		}
-		if (opt->o_set == NULL) {
-			nni_mtx_unlock(&s->s_mx);
-			return (NNG_EREADONLY);
-		}
-		rv = opt->o_set(s, v, sz, t);
+	rv = nni_setopt(sock_options, name, s, v, sz, t);
+	if (rv != NNG_ENOTSUP) {
 		nni_mtx_unlock(&s->s_mx);
 		return (rv);
 	}
-
 	nni_mtx_unlock(&s->s_mx);
 
 	// If the option was already handled one way or the other,
@@ -1103,11 +1087,10 @@ nni_sock_setopt(
 
 int
 nni_sock_getopt(
-    nni_sock *s, const char *name, void *val, size_t *szp, nni_opt_type t)
+    nni_sock *s, const char *name, void *val, size_t *szp, nni_type t)
 {
-	int               rv = NNG_ENOTSUP;
-	nni_sockopt *     sopt;
-	const nni_option *opt;
+	int          rv = NNG_ENOTSUP;
+	nni_sockopt *sopt;
 
 	nni_mtx_lock(&s->s_mx);
 	if (s->s_closing) {
@@ -1118,29 +1101,16 @@ nni_sock_getopt(
 	// Protocol specific options.  The protocol can override
 	// options like the send buffer or notification descriptors
 	// this way.
-	for (opt = s->s_sock_ops.sock_options; opt->o_name != NULL; opt++) {
-		if (strcmp(name, opt->o_name) != 0) {
-			continue;
-		}
-		if (opt->o_get == NULL) {
-			nni_mtx_unlock(&s->s_mx);
-			return (NNG_EWRITEONLY);
-		}
-		rv = opt->o_get(s->s_data, val, szp, t);
+	rv = nni_getopt(
+	    s->s_sock_ops.sock_options, name, s->s_data, val, szp, t);
+	if (rv != NNG_ENOTSUP) {
 		nni_mtx_unlock(&s->s_mx);
 		return (rv);
 	}
 
 	// Socket generic options.
-	for (opt = sock_options; opt->o_name != NULL; opt++) {
-		if (strcmp(name, opt->o_name) != 0) {
-			continue;
-		}
-		if (opt->o_get == NULL) {
-			nni_mtx_unlock(&s->s_mx);
-			return (NNG_EWRITEONLY);
-		}
-		rv = opt->o_get(s, val, szp, t);
+	rv = nni_getopt(sock_options, name, s, val, szp, t);
+	if (rv != NNG_ENOTSUP) {
 		nni_mtx_unlock(&s->s_mx);
 		return (rv);
 	}
@@ -1351,8 +1321,7 @@ nni_ctx_recv(nni_ctx *ctx, nni_aio *aio)
 }
 
 int
-nni_ctx_getopt(
-    nni_ctx *ctx, const char *opt, void *v, size_t *szp, nni_opt_type t)
+nni_ctx_getopt(nni_ctx *ctx, const char *opt, void *v, size_t *szp, nni_type t)
 {
 	nni_sock *  sock = ctx->c_sock;
 	nni_option *o;
@@ -1382,7 +1351,7 @@ nni_ctx_getopt(
 
 int
 nni_ctx_setopt(
-    nni_ctx *ctx, const char *opt, const void *v, size_t sz, nni_opt_type t)
+    nni_ctx *ctx, const char *opt, const void *v, size_t sz, nni_type t)
 {
 	nni_sock *  sock = ctx->c_sock;
 	nni_option *o;
diff --git a/src/core/transport.c b/src/core/transport.c
index 185ab779..da192416 100644
--- a/src/core/transport.c
+++ b/src/core/transport.c
@@ -125,6 +125,11 @@ nni_tran_chkopt(const char *name, const void *v, size_t sz, int typ)
 		// Generally we look for endpoint options. We check both
 		// dialers and listeners.
 		dops = t->t_tran.tran_dialer;
+		if ((dops->d_setopt != NULL) &&
+		    ((rv = dops->d_setopt(NULL, name, v, sz, typ)) !=
+		        NNG_ENOTSUP)) {
+			return (rv);
+		}
 		for (o = dops->d_options; o && o->o_name != NULL; o++) {
 			if (strcmp(name, o->o_name) != 0) {
 				continue;
@@ -138,6 +143,11 @@ nni_tran_chkopt(const char *name, const void *v, size_t sz, int typ)
 			return (rv);
 		}
 		lops = t->t_tran.tran_listener;
+		if ((lops->l_setopt != NULL) &&
+		    ((rv = lops->l_setopt(NULL, name, v, sz, typ)) !=
+		        NNG_ENOTSUP)) {
+			return (rv);
+		}
 		for (o = lops->l_options; o && o->o_name != NULL; o++) {
 			if (strcmp(name, o->o_name) != 0) {
 				continue;
diff --git a/src/core/transport.h b/src/core/transport.h
index 1736f8ea..338b3f67 100644
--- a/src/core/transport.h
+++ b/src/core/transport.h
@@ -27,7 +27,8 @@
 #define NNI_TRANSPORT_V3 0x54520003
 #define NNI_TRANSPORT_V4 0x54520004
 #define NNI_TRANSPORT_V5 0x54520005
-#define NNI_TRANSPORT_VERSION NNI_TRANSPORT_V5
+#define NNI_TRANSPORT_V6 0x54220006
+#define NNI_TRANSPORT_VERSION NNI_TRANSPORT_V6
 
 // Endpoint operations are called by the socket in a
 // protocol-independent fashion.  The socket makes individual calls,
@@ -58,6 +59,12 @@ struct nni_tran_dialer_ops {
 	// nonblocking.
 	void (*d_close)(void *);
 
+	// d_getopt is used to obtain an option.
+	int (*d_getopt)(void *, const char *, void *, size_t *, nni_type);
+
+	// d_setopt is used to set or change an option.
+	int (*d_setopt)(void *, const char *, const void *, size_t, nni_type);
+
 	// d_options is an array of dialer options.  The final
 	// element must have a NULL name. If this member is NULL, then
 	// no dialer specific options are available.
@@ -88,6 +95,12 @@ struct nni_tran_listener_ops {
 	// nonblocking.
 	void (*l_close)(void *);
 
+	// l_getopt is used to obtain an option.
+	int (*l_getopt)(void *, const char *, void *, size_t *, nni_type);
+
+	// l_setopt is used to set or change an option.
+	int (*l_setopt)(void *, const char *, const void *, size_t, nni_type);
+
 	// l_options is an array of listener options.  The final
 	// element must have a NULL name. If this member is NULL, then
 	// no dialer specific options are available.
@@ -137,6 +150,10 @@ struct nni_tran_pipe_ops {
 	// whatever transport specific manner is appropriate.
 	uint16_t (*p_peer)(void *);
 
+	// p_getopt is used to obtain an option.  Pipes don't implement
+	// option setting.
+	int (*p_getopt)(void *, const char *, void *, size_t *, nni_type);
+
 	// p_options is an array of pipe options.  The final element
 	// must have a NULL name. If this member is NULL, then no
 	// transport specific options are available.