查看标准输入 (UTF-8) 里每个字符的 Unicode 编号，类似于 od

runedump.go

/* 查看标准输入 (UTF-8) 里每个字符的 Unicode 编号，类似于 od */

package main

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

const col = 8

func main() {
	inbuf := bufio.NewReader(os.Stdin)
	outbuf := bufio.NewWriter(os.Stdout)
	defer outbuf.Flush()

	line := make([]rune, 0, col)
	for {
		r, _, err := inbuf.ReadRune()
		if err == io.EOF {
			break
		}
		if err != nil {
			fmt.Fprintf(os.Stderr, "%s: %s", os.Args[0], err)
			os.Exit(1)
		}

		fmt.Fprintf(outbuf, "%.4x ", r)
		line = append(line, r)
		if len(line) >= col {
			fmt.Fprintf(outbuf, "%q\n", string(line))
			line = line[:0]
		}
	}
	if len(line) != 0 {
		for i := len(line); i < col; i++ {
			fmt.Fprint(outbuf, "     ")
		}
		fmt.Fprintf(outbuf, "%q\n", string(line))
	}
}