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)
}