pkg io, type ReadSeekCloser interface, Close() error
pkg io, type ReadSeekCloser interface, Read([]uint8) (int, error)
pkg io, type ReadSeekCloser interface, Seek(int64, int) (int64, error)
pkg io, var Discard Writer
pkg io/fs, const ModeAppend = 1073741824
pkg io/fs, const ModeAppend FileMode
pkg io/fs, const ModeCharDevice = 2097152
pkg io/fs, const ModeCharDevice FileMode
pkg io/fs, const ModeDevice = 67108864

<code>-</code>, <code>*</code>, and <code>&lt;&lt;</code> are
computed modulo 2<sup><i>n</i></sup>, where <i>n</i> is the bit width of
the unsigned integer's type.
Loosely speaking, these unsigned integer operations
discard high bits upon overflow, and programs may rely on "wrap around".
</p>

<p>
For signed integers, the operations <code>+</code>,
<code>-</code>, <code>*</code>, <code>/</code>, and <code>&lt;&lt;</code> may legally