go: generate 32 bytes and encode to hex

main.go

package main

import (
        "crypto/rand"
        "encoding/hex"
        "os"
)

func main() {
        // generate 32 bytes key
        d := make([]byte, 32)
        _, err := rand.Read(d)
        if err != nil {
                panic(err)
        }
        os.Stdout.WriteString(hex.EncodeToString(d))
        os.Stdout.WriteString("\n")
}