56 lines
1.4 KiB
ReStructuredText
56 lines
1.4 KiB
ReStructuredText
PR_GetRandomNoise
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=================
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Produces a random value for use as a seed value for another random
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number generator.
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Syntax
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------
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.. code::
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#include <prrng.h>
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NSPR_API(PRSize) PR_GetRandomNoise(
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void *buf,
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PRSize size
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);
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Parameters
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~~~~~~~~~~
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The function has these parameters:
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``buf``
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A pointer to a caller-supplied buffer to contain the generated random
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number. ``buf`` must be at least as large as specified in ``size``.
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``size``
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The size, in bytes, of the requested random number.
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Returns
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~~~~~~~
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:ref:`PRSize` value equal to the size of the random number actually
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generated, or zero. The generated size may be less than the size
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requested. A return value of zero means that :ref:`PR_GetRandomNoise` is
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not implemented on this platform, or there is no available noise to be
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returned at the time of the call.
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Description
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-----------
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:ref:`PR_GetRandomNoise` provides a random value, depending on platform.
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The length of the random value is dependent on the platform and its
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ability to provide a random value at that moment.
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:ref:`PR_GetRandomNoise` is intended to provide a "seed" value for a
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another random number generator that may be suitable for cryptographic
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operations. This implies that the random value provided may not be, by
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itself, cryptographically secure. The value generated by
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:ref:`PR_GetRandomNoise` is at best, extremely difficult to predict and is
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as nondeterministic as the underlying platform permits.
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