1 files changed, 66 insertions, 0 deletions
diff --git a/doc/examples/udp.c b/doc/examples/udp.c
new file mode 100644
index 0000000..989ffcc
--- /dev/null
+++ b/doc/examples/udp.c
@@ -0,0 +1,66 @@
+/* This example code is placed in the public domain. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <unistd.h>
+
+/* udp.c */
+int udp_connect(void);
+void udp_close(int sd);
+
+/* Connects to the peer and returns a socket
+ * descriptor.
+ */
+extern int udp_connect(void)
+{
+        const char *PORT = "5557";
+        const char *SERVER = "127.0.0.1";
+        int err, sd;
+#if defined(IP_DONTFRAG) || defined(IP_MTU_DISCOVER)
+        int optval;
+#endif
+        struct sockaddr_in sa;
+
+        /* connects to server
+         */
+        sd = socket(AF_INET, SOCK_DGRAM, 0);
+
+        memset(&sa, '\0', sizeof(sa));
+        sa.sin_family = AF_INET;
+        sa.sin_port = htons(atoi(PORT));
+        inet_pton(AF_INET, SERVER, &sa.sin_addr);
+
+#if defined(IP_DONTFRAG)
+        optval = 1;
+        setsockopt(sd, IPPROTO_IP, IP_DONTFRAG,
+                   (const void *) &optval, sizeof(optval));
+#elif defined(IP_MTU_DISCOVER)
+        optval = IP_PMTUDISC_DO;
+        setsockopt(sd, IPPROTO_IP, IP_MTU_DISCOVER,
+                   (const void *) &optval, sizeof(optval));
+#endif
+
+        err = connect(sd, (struct sockaddr *) &sa, sizeof(sa));
+        if (err < 0) {
+                fprintf(stderr, "Connect error\n");
+                exit(1);
+        }
+
+        return sd;
+}
+
+/* closes the given socket descriptor.
+ */
+extern void udp_close(int sd)
+{
+        close(sd);
+}