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<h1>Package crc64</h1>
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<dd><code>import "hash/crc64"</code></dd>
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<p>
Package crc64 implements the 64-bit cyclic redundancy check, or CRC-64,
checksum. See <a href="http://en.wikipedia.org/wiki/Cyclic_redundancy_check">http://en.wikipedia.org/wiki/Cyclic_redundancy_check</a> for
information.
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<dd><a href="index.html#pkg-constants">Constants</a></dd>
<dd><a href="index.html#Checksum">func Checksum(data []byte, tab *Table) uint64</a></dd>
<dd><a href="index.html#New">func New(tab *Table) hash.Hash64</a></dd>
<dd><a href="index.html#Update">func Update(crc uint64, tab *Table, p []byte) uint64</a></dd>
<dd><a href="index.html#Table">type Table</a></dd>
<dd>&nbsp; &nbsp; <a href="index.html#MakeTable">func MakeTable(poly uint64) *Table</a></dd>
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<h4>Package files</h4>
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<a href="http://localhost:6060/src/hash/crc64/crc64.go">crc64.go</a>
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<h2 id="pkg-constants">Constants</h2>
<pre>const (
<span class="comment">// The ISO polynomial, defined in ISO 3309 and used in HDLC.</span>
<span id="ISO">ISO</span> = 0xD800000000000000
<span class="comment">// The ECMA polynomial, defined in ECMA 182.</span>
<span id="ECMA">ECMA</span> = 0xC96C5795D7870F42
)</pre>
<p>
Predefined polynomials.
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<pre>const <span id="Size">Size</span> = 8</pre>
<p>
The size of a CRC-64 checksum in bytes.
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<h2 id="Checksum">func <a href="http://localhost:6060/src/hash/crc64/crc64.go?s=2299:2344#L79">Checksum</a></h2>
<pre>func Checksum(data []<a href="../../builtin/index.html#byte">byte</a>, tab *<a href="index.html#Table">Table</a>) <a href="../../builtin/index.html#uint64">uint64</a></pre>
<p>
Checksum returns the CRC-64 checksum of data
using the polynomial represented by the Table.
</p>
<h2 id="New">func <a href="http://localhost:6060/src/hash/crc64/crc64.go?s=1371:1403#L44">New</a></h2>
<pre>func New(tab *<a href="index.html#Table">Table</a>) <a href="../index.html">hash</a>.<a href="../index.html#Hash64">Hash64</a></pre>
<p>
New creates a new hash.Hash64 computing the CRC-64 checksum
using the polynomial represented by the Table.
Its Sum method will lay the value out in big-endian byte order.
</p>
<h2 id="Update">func <a href="http://localhost:6060/src/hash/crc64/crc64.go?s=1777:1829#L61">Update</a></h2>
<pre>func Update(crc <a href="../../builtin/index.html#uint64">uint64</a>, tab *<a href="index.html#Table">Table</a>, p []<a href="../../builtin/index.html#byte">byte</a>) <a href="../../builtin/index.html#uint64">uint64</a></pre>
<p>
Update returns the result of adding the bytes in p to the crc.
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<h2 id="Table">type <a href="http://localhost:6060/src/hash/crc64/crc64.go?s=697:719#L15">Table</a></h2>
<pre>type Table [256]<a href="../../builtin/index.html#uint64">uint64</a></pre>
<p>
Table is a 256-word table representing the polynomial for efficient processing.
</p>
<h3 id="MakeTable">func <a href="http://localhost:6060/src/hash/crc64/crc64.go?s=845:879#L19">MakeTable</a></h3>
<pre>func MakeTable(poly <a href="../../builtin/index.html#uint64">uint64</a>) *<a href="index.html#Table">Table</a></pre>
<p>
MakeTable returns a Table constructed from the specified polynomial.
The contents of this Table must not be modified.
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