# Functions
Executable 和os.Executable() 一致,但是获取执行程序的所在路径和文件名.
FileCopy copies file from source to target path.
FileMode returns file mode and possible error.
FileModTime returns file modified time and possible error.
Filepaths returns all root dir (contain sub dir) file full path.
FileSize returns file size in bytes and possible error.
HasPermission returns a boolean indicating whether that permission is allowed.
IsDir returns true if given path is a dir, or returns false when it's a file or does not exist.
IsExist checks whether a file or directory exists.
IsFile returns true if given path is a file, or returns false when it's a directory or does not exist.
IsLinux 当前操作系统是否Linux.
IsMac 当前操作系统是否Mac OS/X.
IsMachineLittleEndian 判断系统大小端.
IsWindows 当前操作系统是否Windows.
WriteFile writes data to a file named by filename.