// A Buffer can turn a string or a []byte into an io.Reader.
	buf := bytes.NewBufferString("R29waGVycyBydWxlIQ==")
	dec := base64.NewDecoder(base64.StdEncoding, buf)
	io.Copy(os.Stdout, dec)
	// Output: Gophers rule!
}

func ExampleBuffer_Bytes() {
	buf := bytes.Buffer{}
	buf.Write([]byte{'h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd'})
	os.Stdout.Write(buf.Bytes())
	// Output: hello world
}

	b0 := b
	endPos := sw.pos + int64(len(b))
	for endPos > sw.pos && err == nil {
		var nf int // Bytes written in fragment
		dataStart, dataEnd := sw.sp[0].Offset, sw.sp[0].endOffset()
		if sw.pos < dataStart { // In a hole fragment
			bf := b[:min(int64(len(b)), dataStart-sw.pos)]
			nf, err = zeroWriter{}.Write(bf)
		} else { // In a data fragment
			bf := b[:min(int64(len(b)), dataEnd-sw.pos)]
			nf, err = sw.fw.Write(bf)
		}

//		{Offset: 18, Length: 3},  // Data fragment for 18..20
//	}
//	var sph sparseHoles = []sparseEntry{
//		{Offset: 0,  Length: 2},  // Hole fragment for 0..1
//		{Offset: 7,  Length: 11}, // Hole fragment for 7..17
//		{Offset: 21, Length: 4},  // Hole fragment for 21..24
//	}
//
// Then the content of the resulting sparse file with a Header.Size of 25 is:
//

			Size:     1000,
			ModTime:  time.Unix(0, 0),
			Format:   FormatGNU,
		}},
	}, {
		// Generated by Go, works on BSD tar v3.1.2 and GNU tar v.1.27.1.
		file: "testdata/gnu-nil-sparse-hole.tar",
		headers: []*Header{{
			Name:     "sparse.db",
			Typeflag: TypeGNUSparse,
			Size:     1000,
			ModTime:  time.Unix(0, 0),
			Format:   FormatGNU,
		}},
	}, {

		} else { // In a hole fragment
			nf = holeEnd - sr.pos
			if sr.physicalRemaining() == 0 {
				writeLastByte = true
				nf--
			}
			_, err = ws.Seek(nf, io.SeekCurrent)
		}
		sr.pos += nf
		if sr.pos >= holeEnd && len(sr.sp) > 1 {
			sr.sp = sr.sp[1:] // Ensure last fragment always remains
		}
	}

	// If the last fragment is a hole, then seek to 1-byte before EOF, and

It is much more difficult for the C world to have pointers into the Go
world, because the Go garbage collector is unaware of the memory
allocated by C.  The most important consideration is not to
constrain future implementations, so the rule is that Go code can
hand a Go pointer to C code but must separately arrange for
Go to hang on to a reference to the pointer until C is done with it.
*/
package gmp

/*
#cgo LDFLAGS: -lgmp
#include <gmp.h>

						SparseHoles: []sparseEntry{{Offset: 1000, Length: 0}},
					}, nil},
					testWrite{strings.Repeat("0123456789", 100), 1000, nil},
					testClose{},
				},
			}, {
				file: "testdata/gnu-nil-sparse-hole.tar",
				tests: []testFnc{
					testHeader{Header{
						Typeflag:    TypeGNUSparse,
						Name:        "sparse.db",
						Size:        1000,
						SparseHoles: []sparseEntry{{Offset: 0, Length: 1000}},