added golang example

examples/go/go.mod

@@ -0,0 +1,3 @@
+module fwlib/examples/go
+
+go 1.15

examples/go/main.go

@@ -0,0 +1,54 @@
+package main
+
+/*
+#cgo CFLAGS: -I./src
+#cgo LDFLAGS: -L./../../ -lfwlib32 -Wl,-rpath=./../../
+#include <stdlib.h>
+#include "../../fwlib32.h"
+*/
+import "C"
+
+import (
+	"fmt"
+	"unsafe"
+)
+
+func main() {
+	var libh C.ushort
+
+	log_level := 0
+	log_fname := C.CString("focas.log")
+	defer C.free(unsafe.Pointer(log_fname))
+	if ret := C.cnc_startupprocess(C.long(log_level), log_fname); ret != C.EW_OK {
+		fmt.Printf("cnc_startupprocess failed (%d)\n", ret)
+		return
+	}
+
+	ip := "localhost"
+	port := 8193
+	_ip := C.CString(ip)
+	defer C.free(unsafe.Pointer(_ip))
+
+	fmt.Printf("connecting to %s:%d...\n", ip, port)
+	if ret := C.cnc_allclibhndl3(_ip, C.ushort(port), 10, &libh); ret != C.EW_OK {
+		fmt.Printf("cnc_allclibhndl3 failed (%d)\n", ret)
+		return
+	}
+
+	var cnc_ids [4]uint32
+	if ret := C.cnc_rdcncid(libh, (*C.ulong)(unsafe.Pointer(&cnc_ids[0]))); ret != C.EW_OK {
+		fmt.Printf("cnc_rdcncid failed (%d)\n", ret)
+		return
+	}
+	machine_id := fmt.Sprintf("%08x-%08x-%08x-%08x", cnc_ids[0], cnc_ids[1], cnc_ids[2], cnc_ids[3])
+
+	fmt.Printf("machine_id: %s\n", machine_id)
+
+	if ret := C.cnc_freelibhndl(libh); ret != C.EW_OK {
+		fmt.Printf("cnc_freelibhndl failed (%d)\n", ret)
+	}
+
+	if ret := C.cnc_exitprocess(); ret != C.EW_OK {
+		fmt.Printf("cnc_exitprocess failed (%d)\n", ret)
+	}
+}