Add cgo-libzmq/README.md

cgo-libzmq/README.md

@@ -0,0 +1,85 @@
+# server.go
+```go
+package main
+
+/*
+#cgo pkg-config: libzmq
+#include <zmq.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <assert.h>
+#include <malloc.h>
+*/
+import "C"
+// sudo apt-get install libzmq3-dev
+import (
+	"unsafe"
+	"fmt"
+)
+
+func main() {
+	context := C.zmq_ctx_new()
+	defer C.zmq_ctx_destroy(context)
+
+	responder := C.zmq_socket(context, C.ZMQ_REP)
+	defer C.zmq_close(responder)
+
+	rc := C.zmq_bind(responder, C.CString("tcp://*:5555"))
+	if rc != 0 {
+		panic("Failed to bind socket")
+	}
+
+	for {
+		buffer := make([]byte, 10)
+		C.zmq_recv(responder, unsafe.Pointer(&buffer[0]), 10, 0)
+		fmt.Println("Received Hello")
+		C.sleep(1)
+		message := unsafe.Pointer(C.CString("World"))
+		defer C.free(message)
+		C.zmq_send(responder, message, 5, 0)
+	}
+}
+```
+
+# client.go
+```go
+package main
+/*
+#cgo pkg-config: libzmq
+#include <zmq.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+*/
+import "C"
+import (
+	"fmt"
+	"unsafe"
+)
+
+func main(){
+	fmt.Println("Connecting to hello world server…")
+	
+	context := C.zmq_ctx_new()
+	defer C.zmq_ctx_destroy(context)
+
+	requester := C.zmq_socket(context, C.ZMQ_REQ)
+	defer C.zmq_close(requester)
+
+	C.zmq_connect(requester, C.CString("tcp://localhost:5555"))
+
+	// for request_nbr := range 10 {
+	
+	for request_nbr := 0; request_nbr < 10; request_nbr++ {
+		buffer := make([]byte, 10)
+		fmt.Printf("Sending Hello %d...\n", request_nbr)
+		msg := unsafe.Pointer(C.CString("Hello"))
+		defer C.free(msg)
+		C.zmq_send(requester, msg, 5, 0);
+		C.zmq_recv(requester, unsafe.Pointer(&buffer[0]), 10, 0);
+		fmt.Printf("Received World %d\n", request_nbr)
+	}
+}
+```