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11<h1 align="left">MATH_CRC*GetHash <img src="../../image/NTR.gif"align="middle"><img src="../../image/TWL.gif" align="middle"></H1>
12<H2>Syntax</H2>
13<dl>
14  <dd>
15  <PRE><CODE>#include &lt;nitro/math/crc.h&gt;
16static inline u8 MATH_CRC8GetHash( <A href="MATHCRCContext.html">MATHCRC8Context</A> *context );
17static inline u16 MATH_CRC16GetHash( <A href="MATHCRCContext.html">MATHCRC16Context</A> *context );
18static inline u16 MATH_CRC16CCITTGetHash( <A href="MATHCRCContext.html">MATHCRC16Context</A> *context );
19static inline u32 MATH_CRC32GetHash( <A href="MATHCRCContext.html">MATHCRC32Context</A> *context );
20static inline u32 MATH_CRC32POSIXGetHash( <A href="MATHCRCContext.html">MATHCRC32Context</A> *context );
21</CODE></PRE>
22  </dd>
23</dl><h2>Arguments</h2>
24<table border="1" width="100%">
25    <TR>
26      <TD width="176"><em><strong><font face="Courier New"><em><strong><code>context</code></strong></em>&nbsp;&nbsp;</font></strong></em></TD>
27      <TD width="670">Pointer to the context structure for CRC* generation.</TD>
28    </TR>
29  </table>
30<h2>Return Values</h2>
31<p>None.</p>
32<H2>Description</H2>
33<P>Obtains the hash value based on various CRCs. You must use a <CODE><A href="MATH_CRCInit.html">MATH_CRC*Init</A></CODE> function to initialize the <CODE>context</CODE> argument, and then use a <CODE><A href="MATH_CRCUpdate.html">MATH_CRC*Update</A></CODE> function to provide the input data.<BR><BR> CRC-8 is an algorithm that finds an 8-bit hash value.<BR> CRC-16 and CRC-16/CCITT are algorithms that find 16-bit hash values.<BR> CRC-32 and CRC-32/POSIX are algorithms that find 32-bit hash values. CRC-16 is the algorithm used in the ARC and LHA compression programs. One restriction is that the hash value does not change when a <code>0</code> byte is appended to the top. CRC-16/CCITT is an algorithm that is used in many data link layer standards as a FCS (Frame Check Sequence). It is defined in the x.25 standard of the CCITT (Comite Consultatif International Telegraphique et Telephonique). CRC-32 is an algorithm used in compression programs, such as PKZIP, and image formats, such as PNG. For details, see ISO 3309 and RFC 2083. CRC-32/POSIX is an algorithm used in the cksum command, which is included in POSIX-compliant Unix. It is defined in POSIX 1003.2. With the <code>cksum</code> command, CRC is taken after the file length is appended to the end of the input file.
34</P>
35<h2>See Also</h2>
36<P><a href="MATH_CRCInit.html"><code>MATH_CRC*Init</code></a><BR> <a href="MATH_CRCUpdate.html"><code>MATH_CRC*Update</code></a></P>
37<H2>Revision History</H2>
38<P>
392005/04/12 Initial version.
40</P>
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