From f43bdcf464d082df0ba273931e76faab81042dfb Mon Sep 17 00:00:00 2001
From: John Safranek <john@wolfssl.com>
Date: Fri, 18 Sep 2026 13:46:35 -0700
Subject: [PATCH] io.c: use the zsock names on Zephyr 4.1 and newer

Zephyr 4.1 dropped CONFIG_NET_SOCKETS_POSIX_NAMES, and from 4.4 the
POSIX aliases in <zephyr/net/socket.h> need a compat mode wolfSSH does
not set, so wsEmbedSend() and wsEmbedRecv() no longer found send() and
recv(). Call zsock_send() and zsock_recv(), which Zephyr declares in
every configuration, and include <zephyr/version.h> for the test.
---
 src/io.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/io.c b/src/io.c
index ffe8e2fdf..563cc8c25 100644
--- a/src/io.c
+++ b/src/io.c
@@ -142,6 +142,7 @@ void* wolfSSH_GetIOWriteCtx(WOLFSSH* ssh)
         #include <errno.h>
     #elif defined(WOLFSSH_ZEPHYR)
         #include <zephyr/net/socket.h>
+        #include <zephyr/version.h>
     #else
         #include <sys/types.h>
         #include <errno.h>
@@ -258,6 +259,15 @@ void* wolfSSH_GetIOWriteCtx(WOLFSSH* ssh)
 #elif defined(WOLFSSL_NUCLEUS)
     #define SEND_FUNCTION NU_Send
     #define RECV_FUNCTION NU_Recv
+#elif defined(WOLFSSH_ZEPHYR)
+    #if KERNEL_VERSION_NUMBER >= 0x40100
+        /* Zephyr 4.1 dropped the POSIX socket names; zsock_ is always there. */
+        #define SEND_FUNCTION zsock_send
+        #define RECV_FUNCTION zsock_recv
+    #else
+        #define SEND_FUNCTION send
+        #define RECV_FUNCTION recv
+    #endif
 #else
     #define SEND_FUNCTION send
     #define RECV_FUNCTION recv