add printer

vo.go

@@ -0,0 +1,31 @@
+package main
+
+import (
+	"C"
+	"encoding/json"
+	"log"
+)
+
+type Reply struct {
+	Status int         `json:"status"`
+	Err    string      `json:"err"`
+	Result interface{} `json:"result"`
+}
+
+func NewErr(err error) *C.char {
+	e := Reply{Status: 1, Err: err.Error()}
+	b, err := json.Marshal(e)
+	if err != nil {
+		log.Println("Error json.Marshal:", err.Error())
+	}
+	return C.CString(string(b))
+}
+
+func NewOk(data interface{}) *C.char {
+	e := Reply{Status: 0, Result: data}
+	b, err := json.Marshal(e)
+	if err != nil {
+		log.Println("Error json.Marshal:", err.Error())
+	}
+	return C.CString(string(b))
+}