The Go code can then refer to types such as C.size_t, variables such
as C.stdout, or functions such as C.putchar.

If the import of "C" is immediately preceded by a comment, that
comment, called the preamble, is used as a header when compiling
the C parts of the package. For example:

	// #include <stdio.h>
	// #include <errno.h>
	import "C"

The preamble may contain any C code, including function and variable

// For forward compatibility, users that retrieve a Header from Reader.Next,
// mutate it in some ways, and then pass it back to Writer.WriteHeader
// should do so by creating a new Header and copying the fields
// that they are interested in preserving.
type Header struct {
	// Typeflag is the type of header entry.
	// The zero value is automatically promoted to either TypeReg or TypeDir
	// depending on the presence of a trailing slash in Name.

denial of service attacks, this setting and default was backported to Go
1.19.13, Go 1.20.8, and Go 1.21.1.

Go 1.22 made it an error for a request or response read by a net/http
client or server to have an empty Content-Length header.
This behavior is controlled by the `httplaxcontentlength` setting.

Go 1.22 changed the behavior of ServeMux to accept extended
patterns and unescape both patterns and request paths by segment.

	}
}

func testValidHeader(h *FileHeader, t *testing.T) {
	var buf bytes.Buffer
	z := NewWriter(&buf)

	f, err := z.CreateHeader(h)
	if err != nil {
		t.Fatalf("error creating header: %v", err)
	}
	if _, err := f.Write([]byte("hi")); err != nil {
		t.Fatalf("error writing content: %v", err)
	}
	if err := z.Close(); err != nil {
		t.Fatalf("error closing zip writer: %v", err)
	}

	}{{
		header:  &Header{},
		formats: FormatUSTAR | FormatPAX | FormatGNU,
	}, {
		header:  &Header{Size: 077777777777},
		formats: FormatUSTAR | FormatPAX | FormatGNU,
	}, {
		header:  &Header{Size: 077777777777, Format: FormatUSTAR},
		formats: FormatUSTAR,
	}, {
		header:  &Header{Size: 077777777777, Format: FormatPAX},
		formats: FormatUSTAR | FormatPAX,
	}, {

			}
			if hdr.Typeflag == TypeXGlobalHeader {
				mergePAX(hdr, paxHdrs)
				return &Header{
					Name:       hdr.Name,
					Typeflag:   hdr.Typeflag,
					Xattrs:     hdr.Xattrs,
					PAXRecords: hdr.PAXRecords,
					Format:     format,
				}, nil
			}
			continue // This is a meta header affecting the next header
		case TypeGNULongName, TypeGNULongLink:
			format.mayOnlyBe(FormatGNU)

type Writer struct {
	cw          *countWriter
	dir         []*header
	last        *fileWriter
	closed      bool
	compressors map[uint16]Compressor
	comment     string

	// testHookCloseSizeOffset if non-nil is called with the size
	// of offset of the central directory at Close.
	testHookCloseSizeOffset func(size, offset uint64)
}

type header struct {
	*FileHeader
	offset uint64
	raw    bool
}