50 lines
1.4 KiB
Markdown
50 lines
1.4 KiB
Markdown
# PR_GetRandomNoise
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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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```{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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```
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### Parameters
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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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{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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{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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