Go语言单个文件拷贝演示代码
package main
import "fmt"
import "io"
import "os"
func main(){
	w,err := CopyFile("filecopy.go","test.go")
	if err!=nil{
		fmt.Println(err.Error())
	}
	fmt.Println(w)
}
func CopyFile(src,dst string)(w int64,err error){
	srcFile,err := os.Open(src)
	if err!=nil{
		fmt.Println(err.Error())
		return
	}
	defer srcFile.Close()
	dstFile,err := os.Create(dst)
	if err!=nil{
		fmt.Println(err.Error())
		return
	}
	defer dstFile.Close()
	return io.Copy(dstFile,srcFile)
}




