close(fds[i]);
 }
 
+#define MSG_PEEK_BUF_LEN 64
+
 static void test_stream_msg_peek_client(const struct test_opts *opts)
 {
+       unsigned char buf[MSG_PEEK_BUF_LEN];
+       ssize_t send_size;
        int fd;
+       int i;
 
        fd = vsock_stream_connect(opts->peer_cid, 1234);
        if (fd < 0) {
                exit(EXIT_FAILURE);
        }
 
-       send_byte(fd, 1, 0);
+       for (i = 0; i < sizeof(buf); i++)
+               buf[i] = rand() & 0xFF;
+
+       control_expectln("SRVREADY");
+
+       send_size = send(fd, buf, sizeof(buf), 0);
+
+       if (send_size < 0) {
+               perror("send");
+               exit(EXIT_FAILURE);
+       }
+
+       if (send_size != sizeof(buf)) {
+               fprintf(stderr, "Invalid send size %zi\n", send_size);
+               exit(EXIT_FAILURE);
+       }
+
        close(fd);
 }
 
 static void test_stream_msg_peek_server(const struct test_opts *opts)
 {
+       unsigned char buf_half[MSG_PEEK_BUF_LEN / 2];
+       unsigned char buf_normal[MSG_PEEK_BUF_LEN];
+       unsigned char buf_peek[MSG_PEEK_BUF_LEN];
+       ssize_t res;
        int fd;
 
        fd = vsock_stream_accept(VMADDR_CID_ANY, 1234, NULL);
                exit(EXIT_FAILURE);
        }
 
-       recv_byte(fd, 1, MSG_PEEK);
-       recv_byte(fd, 1, 0);
+       /* Peek from empty socket. */
+       res = recv(fd, buf_peek, sizeof(buf_peek), MSG_PEEK | MSG_DONTWAIT);
+       if (res != -1) {
+               fprintf(stderr, "expected recv(2) failure, got %zi\n", res);
+               exit(EXIT_FAILURE);
+       }
+
+       if (errno != EAGAIN) {
+               perror("EAGAIN expected");
+               exit(EXIT_FAILURE);
+       }
+
+       control_writeln("SRVREADY");
+
+       /* Peek part of data. */
+       res = recv(fd, buf_half, sizeof(buf_half), MSG_PEEK);
+       if (res != sizeof(buf_half)) {
+               fprintf(stderr, "recv(2) + MSG_PEEK, expected %zu, got %zi\n",
+                       sizeof(buf_half), res);
+               exit(EXIT_FAILURE);
+       }
+
+       /* Peek whole data. */
+       res = recv(fd, buf_peek, sizeof(buf_peek), MSG_PEEK);
+       if (res != sizeof(buf_peek)) {
+               fprintf(stderr, "recv(2) + MSG_PEEK, expected %zu, got %zi\n",
+                       sizeof(buf_peek), res);
+               exit(EXIT_FAILURE);
+       }
+
+       /* Compare partial and full peek. */
+       if (memcmp(buf_half, buf_peek, sizeof(buf_half))) {
+               fprintf(stderr, "Partial peek data mismatch\n");
+               exit(EXIT_FAILURE);
+       }
+
+       res = recv(fd, buf_normal, sizeof(buf_normal), 0);
+       if (res != sizeof(buf_normal)) {
+               fprintf(stderr, "recv(2), expected %zu, got %zi\n",
+                       sizeof(buf_normal), res);
+               exit(EXIT_FAILURE);
+       }
+
+       /* Compare full peek and normal read. */
+       if (memcmp(buf_peek, buf_normal, sizeof(buf_peek))) {
+               fprintf(stderr, "Full peek data mismatch\n");
+               exit(EXIT_FAILURE);
+       }
+
        close(fd);
 }