literal, or by taking the address of a local variable may also have their
memory pinned using [runtime.Pinner]. This type may be used to manage
the duration of the memory's pinned status, potentially beyond the
duration of a C function call. Memory may be pinned more than once and
must be unpinned exactly the same number of times it has been pinned.

Go code may pass a Go pointer to C provided the memory to which it

	if !ok {
		m = b.grow(len(s))
	}
	return copy(b.buf[m:], s), nil
}

// MinRead is the minimum slice size passed to a Read call by
// [Buffer.ReadFrom]. As long as the [Buffer] has at least MinRead bytes beyond
// what is required to hold the contents of r, ReadFrom will not grow the
// underlying buffer.
const MinRead = 512

// ReadFrom reads data from r until EOF and appends it to the buffer, growing

			return false // Negative values are never okay
		case cur.Offset > math.MaxInt64-cur.Length:
			return false // Integer overflow with large length
		case cur.endOffset() > size:
			return false // Region extends beyond the actual size
		case pre.endOffset() > cur.Offset:
			return false // Regions cannot overlap and must be in order
		}
		pre = cur
	}
	return true
}

	ErrTooLong         = errors.New("bufio.Scanner: token too long")
	ErrNegativeAdvance = errors.New("bufio.Scanner: SplitFunc returns negative advance count")
	ErrAdvanceTooFar   = errors.New("bufio.Scanner: SplitFunc returns advance count beyond input")
	ErrBadReadCount    = errors.New("bufio.Scanner: Read returned impossible count")
)

const (
	// MaxScanTokenSize is the maximum size used to buffer a token