fn preadvAll(self: File, iovecs: []os.iovec, offset: u64) PReadError!usize

Returns the number of bytes read. If the number read is smaller than the total bytes from all the buffers, it means the file reached the end. Reaching the end of a file is not an error condition. The iovecs parameter is mutable because this function needs to mutate the fields in order to handle partial reads from the underlying OS layer. See https://github.com/ziglang/zig/issues/7699 On Windows, this function currently does alter the file pointer. https://github.com/ziglang/zig/issues/12783

Parameters

self: File,
iovecs: []os.iovec,
offset: u64,