import (
	"bufio"
	"bytes"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func ExampleWriter() {
	w := bufio.NewWriter(os.Stdout)
	fmt.Fprint(w, "Hello, ")
	fmt.Fprint(w, "world!")
	w.Flush() // Don't forget to flush!
	// Output: Hello, world!
}

func ExampleWriter_AvailableBuffer() {
	w := bufio.NewWriter(os.Stdout)
	for _, i := range []int64{1, 2, 3, 4} {
		b := w.AvailableBuffer()
		b = strconv.AppendInt(b, i, 10)

	log.SetPrefix("mkzip: ")
	log.SetFlags(0)
	flag.Usage = usage
	flag.Parse()
	args := flag.Args()
	if len(args) != 1 || !strings.HasSuffix(args[0], ".zip") {
		usage()
	}

	var zb bytes.Buffer
	zw := zip.NewWriter(&zb)
	seen := make(map[string]bool)
	err := filepath.WalkDir(".", func(path string, d fs.DirEntry, err error) error {
		if d.IsDir() {
			return nil
		}
		data, err := os.ReadFile(path)
		if err != nil {

	"sort"
	"strings"
	"testing"
	"time"
)

func TestOver65kFiles(t *testing.T) {
	if testing.Short() && testenv.Builder() == "" {
		t.Skip("skipping in short mode")
	}
	buf := new(strings.Builder)
	w := NewWriter(buf)
	const nFiles = (1 << 16) + 42
	for i := 0; i < nFiles; i++ {
		_, err := w.CreateHeader(&FileHeader{
			Name:   fmt.Sprintf("%d.dat", i),
			Method: Store, // Deflate is too slow when it is compiled with -race flag

	case "index":
		// known to compiler; ignore here so people can use
		// the same list with -gcflags=-spectre=LIST and -asmflags=-spectrre=LIST
	case "all", "ret":
		ctxt.Retpoline = true
	}

	ctxt.Bso = bufio.NewWriter(os.Stdout)
	defer ctxt.Bso.Flush()

	architecture.Init(ctxt)

	// Create object file, write header.
	buf, err := bio.Create(*flags.OutputFile)
	if err != nil {
		log.Fatal(err)
	}
	defer buf.Close()

package tar_test

import (
	"archive/tar"
	"bytes"
	"fmt"
	"io"
	"log"
	"os"
)

func Example_minimal() {
	// Create and add some files to the archive.
	var buf bytes.Buffer
	tw := tar.NewWriter(&buf)
	var files = []struct {
		Name, Body string
	}{
		{"readme.txt", "This archive contains some text files."},
		{"gopher.txt", "Gopher names:\nGeorge\nGeoffrey\nGonzo"},

	// Create a buffer to write our archive to.
	buf := new(bytes.Buffer)

	// Create a new zip archive.
	w := zip.NewWriter(buf)

	// Register a custom Deflate compressor.
	w.RegisterCompressor(zip.Deflate, func(out io.Writer) (io.WriteCloser, error) {
		return flate.NewWriter(out, flate.BestCompression)
	})

	// Proceed to add files to w.

	// write a zip file
	archive := new(bytes.Buffer)
	w := NewWriter(archive)

	for i := range files {
		f := &files[i]
		f.crc32 = crc32.ChecksumIEEE(f.content)
		size := uint64(len(f.content))
		f.uncompressedSize = size
		f.compressedSize = size

		var compressedContent []byte
		if f.method == Deflate {
			var buf bytes.Buffer
			w, err := flate.NewWriter(&buf, flate.BestSpeed)
			if err != nil {

		t.Errorf("NewReaderSize's Reader.Size = %d; want %d", got, want)
	}
}

func TestWriterSize(t *testing.T) {
	if got, want := NewWriter(nil).Size(), DefaultBufSize; got != want {
		t.Errorf("NewWriter's Writer.Size = %d; want %d", got, want)
	}
	if got, want := NewWriterSize(nil, 1234).Size(), 1234; got != want {
		t.Errorf("NewWriterSize's Writer.Size = %d; want %d", got, want)
	}

	// err is a persistent error.
	// It is only the responsibility of every exported method of Writer to
	// ensure that this error is sticky.
	err error
}

// NewWriter creates a new Writer writing to w.
func NewWriter(w io.Writer) *Writer {
	return &Writer{w: w, curr: &regFileWriter{w, 0}}
}

type fileWriter interface {
	io.Writer
	fileState

	ReadFrom(io.Reader) (int64, error)
}

				continue
			}
		}

		// If we were unable to read anything out of the archive don't
		// bother trying to roundtrip it.
		if len(files) == 0 {
			return
		}

		w := NewWriter(io.Discard)
		for _, f := range files {
			ww, err := w.CreateHeader(f.header)
			if err != nil {
				t.Fatalf("unable to write previously parsed header: %s", err)
			}
			if _, err := ww.Write(f.content); err != nil {