return n, nil // e is EOF, so return nil explicitly
		}
		if e != nil {
			return n, e
		}
	}
}

// growSlice grows b by n, preserving the original content of b.
// If the allocation fails, it panics with ErrTooLarge.
func growSlice(b []byte, n int) []byte {
	defer func() {
		if recover() != nil {
			panic(ErrTooLarge)
		}
	}()

// getFormat checks that the block is a valid tar header based on the checksum.
// It then attempts to guess the specific format based on magic values.
// If the checksum fails, then FormatUnknown is returned.
func (b *block) getFormat() Format {
	// Verify checksum.
	var p parser
	value := p.parseOctal(b.toV7().chksum())
	chksum1, chksum2 := b.computeChecksum()

				return i
			}
			fails++
			i++
			// Switch to bytealg.Index when IndexByte produces too many false positives.
			if fails > bytealg.Cutover(i) {
				r := bytealg.Index(s[i:], sep)
				if r >= 0 {
					return r + i
				}
				return -1
			}
		}
		return -1
	}
	c0 := sep[0]
	c1 := sep[1]
	i := 0
	fails := 0
	t := len(s) - n + 1
	for i < t {

	hdr, err := FileInfoHeader(fileinfo, "")
	if err != nil {
		t.Fatalf("os.Stat:1 %v", err)
	}
	hdr.Typeflag = TypeDir
	// Force a PAX long name to be written. The name was taken from a practical example
	// that fails and replaced ever char through numbers to anonymize the sample.

// The bytes stop being valid at the next read.
// If ReadSlice encounters an error before finding a delimiter,
// it returns all the data in the buffer and the error itself (often io.EOF).
// ReadSlice fails with error [ErrBufferFull] if the buffer fills without a delim.
// Because the data returned from ReadSlice will be overwritten
// by the next I/O operation, most clients should use
// [Reader.ReadBytes] or ReadString instead.

	attempt := 0
	for {
		cmd := idevCmd(exec.Command(
			"ideviceinstaller",
			"-i", appdir,
		))
		if out, err := cmd.CombinedOutput(); err != nil {
			// Sometimes, installing the app fails for some reason.
			// Give the device a few seconds and try again.
			if attempt < 5 {
				time.Sleep(5 * time.Second)
				attempt++
				continue
			}
			os.Stderr.Write(out)