Function readPositional [src]

Prototype

pub fn readPositional(r: *Reader, dest: []u8) std.Io.Reader.Error!usize

Parameters

r: *Readerdest: []u8

Source

  pub fn readPositional(r: *Reader, dest: []u8) std.Io.Reader.Error!usize {
    const n = r.file.pread(dest, r.pos) catch |err| switch (err) {
        error.Unseekable => {
            r.mode = r.mode.toStreaming();
            const pos = r.pos;
            if (pos != 0) {
                r.pos = 0;
                r.seekBy(@intCast(pos)) catch {
                    r.mode = .failure;
                    return error.ReadFailed;
                };
            }
            return 0;
        },
        else => |e| {
            r.err = e;
            return error.ReadFailed;
        },
    };
    if (n == 0) {
        r.size = r.pos;
        return error.EndOfStream;
    }
    r.pos += n;
    return n;
}  