Go conversion between struct and byte array

Question

I am writing a client - server application in Go. I want to perform C-like type casting in Go.

E.g. in Go

type packet struct {
    opcode uint16
             


        

Answer 1

unsafe.Pointer is, well, unsafe, and you don't actually need it here. Use encoding/binary package instead:

// Create a struct and write it.
t := T{A: 0xEEFFEEFF, B: 3.14}
buf := &bytes.Buffer{}
err := binary.Write(buf, binary.BigEndian, t)
if err != nil {
    panic(err)
}
fmt.Println(buf.Bytes())

// Read into an empty struct.
t = T{}
err = binary.Read(buf, binary.BigEndian, &t)
if err != nil {
    panic(err)
}
fmt.Printf("%x %f", t.A, t.B)

Playground

As you can see, it handles sizes and endianness quite neatly.