read file using go

read.go

/*
from https://stackoverflow.com/questions/14514201/how-to-read-a-binary-file-in-go
*/
package main

import (
    "fmt"
    "io"
    "os"
)

func main() {
    f, err := os.Open("filename")
    if err != nil {
        fmt.Println(err)
        return
    }
    defer f.Close()
    data := make([]byte, 4096)
    zeroes := 0
    for {
        data = data[:cap(data)]
        n, err := f.Read(data)
        if err != nil {
            if err == io.EOF {
                break
            }
            fmt.Println(err)
            return
        }
        data = data[:n]
        for _, b := range data {
            if b == 0 {
                zeroes++
            }
        }
    }
    fmt.Println("zeroes:", zeroes)
}