go语言实现文件分割的方法

本文实例讲述了go语言实现文件分割的方法。分享给大家供大家参考。具体实现方法如下：

import (
 // "bufio"
 "flag"
 "fmt"
 "io"
 "os"
)
import "strconv"
var infile *string = flag.string("f", "null", "please input a file name or dir.")
var size *string = flag.string("s", "0", "please input a dst file size.")
//func datacopy(file *os.file, file *os.file)
func splitfile(file *os.file, size int) {
 finfo, err := file.stat()
 if err != nil {
  fmt.println("get file info failed:", file, size)
 }
 fmt.println(finfo, size)
 //每次最多拷贝1m
 bufsize := 1024 * 1024
 if size < bufsize {
  bufsize = size
 }
 buf := make([]byte, bufsize)
 num := (int(finfo.size()) + size - 1) / size
 fmt.println(num, len(buf))
 for i := 0; i < num; i++ {
  copylen := 0
  newfilename := finfo.name() + strconv.itoa(i)
  newfile, err1 := os.create(newfilename)
  if err1 != nil {
   fmt.println("failed to create file", newfilename)
  } else {
   fmt.println("create file:", newfilename)
  }
  for copylen < size {
   n, err2 := file.read(buf)
   if err2 != nil && err2 != io.eof {
    fmt.println(err2, "failed to read from:", file)
    break
   }
   if n <= 0 {
    break
   }
   //fmt.println(n, len(buf))
   //写文件
   w_buf := buf[:n]
   newfile.write(w_buf)
   copylen += n
  }
 }

 return
}
func main() {
 flag.parse()
 if *infile == "null" {
  fmt.println("no file to input")
  return
 }
 file, err := os.open(*infile)
 if err != nil {
  fmt.println("failed to open:", *infile)
 }
 defer file.close()
 size, _ := strconv.atoi(*size)
 splitfile(file, size*1024)
}

希望本文所述对大家的go语言程序设计有所帮助。