gistfile1.go

package main

import (
	"bytes"
	"fmt"
	"io"
)

type BytesReadCloser struct {
	*bytes.Reader
}

func NewBytesReadCloser(b []byte) io.ReadCloser {
	return BytesReadCloser{bytes.NewReader(b)}
}

func (brc BytesReadCloser) Close() error {
	return nil
}

func testReadCloser(rc io.ReadCloser) {
	var b[5] byte
	rc.Read(b[:])
	rc.Close()
	fmt.Println(string(b[:]))
}

func main() {
	brc := NewBytesReadCloser([]byte("hello world"))
	testReadCloser(brc)
}