Golang的_byteswap_ulong

Question

What is the equivalent of _byteswap_ulong in Golang? Does it exist as a package?

I tried to use the binary package and play with the reader, but couldn't get it working. I need to swap bytes in a uint64 variable.

Input is 2832779. Output should be 8b392b.

Answer 1

As @David said, use the binary.ByteOrder type

package main

import (
    "encoding/binary"
    "fmt"
)

func main() {
    value := make([]byte, 4)

    // need to know the byte ordering ahead of time
    binary.LittleEndian.PutUint32(value, 0x12345678)

    fmt.Printf("%#v
", value)

    fmt.Printf("Big Endian Representation, 0x%X
", binary.BigEndian.Uint32(value))
    fmt.Printf("Little Endian Representation, 0x%X
", binary.LittleEndian.Uint32(value))
}

Playground link

This will output:

[]byte{0x78, 0x56, 0x34, 0x12}
Big Endian Representation, 0x78563412
Little Endian Representation, 0x12345678

These are the big-endian and little-endian representations on a little-endian server.