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Previous: <a href="Quality-of-random-numbers.html#Quality-of-random-numbers" accesskey="p" rel="prev">Quality of random numbers</a>, Up: <a href="Random-Numbers.html#Random-Numbers" accesskey="u" rel="up">Random Numbers</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Retrieving-random-numbers-1"></a>
<h3 class="section">10.2 Retrieving random numbers</h3>
<dl>
<dt><a name="index-gcry_005frandomize"></a>Function: <em>void</em> <strong>gcry_randomize</strong> <em>(unsigned char *<var>buffer</var>, size_t <var>length</var>, enum gcry_random_level <var>level</var>)</em></dt>
<dd>
<p>Fill <var>buffer</var> with <var>length</var> random bytes using a random quality
as defined by <var>level</var>.
</p></dd></dl>
<dl>
<dt><a name="index-gcry_005frandom_005fbytes"></a>Function: <em>void *</em> <strong>gcry_random_bytes</strong> <em>(size_t <var>nbytes</var>, enum gcry_random_level <var>level</var>)</em></dt>
<dd>
<p>Convenience function to allocate a memory block consisting of
<var>nbytes</var> fresh random bytes using a random quality as defined by
<var>level</var>.
</p></dd></dl>
<dl>
<dt><a name="index-gcry_005frandom_005fbytes_005fsecure"></a>Function: <em>void *</em> <strong>gcry_random_bytes_secure</strong> <em>(size_t <var>nbytes</var>, enum gcry_random_level <var>level</var>)</em></dt>
<dd>
<p>Convenience function to allocate a memory block consisting of
<var>nbytes</var> fresh random bytes using a random quality as defined by
<var>level</var>. This function differs from <code>gcry_random_bytes</code> in
that the returned buffer is allocated in a “secure” area of the
memory.
</p></dd></dl>
<dl>
<dt><a name="index-gcry_005fcreate_005fnonce"></a>Function: <em>void</em> <strong>gcry_create_nonce</strong> <em>(unsigned char *<var>buffer</var>, size_t <var>length</var>)</em></dt>
<dd>
<p>Fill <var>buffer</var> with <var>length</var> unpredictable bytes. This is
commonly called a nonce and may also be used for initialization
vectors and padding. This is an extra function nearly independent of
the other random function for 3 reasons: It better protects the
regular random generator’s internal state, provides better performance
and does not drain the precious entropy pool.
</p>
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