拷贝文件

package main
import(
	"fmt"
	"io"
	"os"
)

func main(){
	CopyFile("target.txt", "source.txt")
	fmt.Println("Copy done!")
}
func CopyFile(dstName, srcName string) (written int 64, err error) {
	src, err := os.Open(srcName)//打开源文件
	if err != nil{
		return
	}
	defer src.Close()
	dst, err := os.OpenFile(dstName, os.O_WRONLY|os.O_CREATE, 0644)//创建目标文件
	if err != nil{
		return
	}
	defer src.Close()
	return io.Copy(dst, src)
}