vectorio is a library for Go (aka "golang") to implement the writev(2), and in the future, readv(2) system calls. This enables a list of byte slices to be efficiently written to a file without first copying them to an intermediate buffer. Go's built-in bufio library is the standard approach to buffered I/O, but vectorio can be a replacement to achieve the same goal but without copying data.

    // Create a temp file to use
    f, _ := ioutil.TempFile("", "vectorio")
    defer f.Close()

    data1 := []byte("foobarbaz")
    data2 := []byte("foobazbar")

    w, _ := vectorio.NewBufferedWritev(f)
    w.Write(data2)
    w.WriteIovec(syscall.Iovec{&data1[0], 9})
    nw, _ := w.Flush()

    fmt.Println("Wrote", nw, "bytes to file!")