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40 ** prrng.h -- NSPR Random Number Generator
54 ** PR_GetRandomNoise() -- Get random noise from the host platform
57 ** PR_GetRandomNoise() provides, depending on platform, a random value.
58 ** The length of the random value is dependent on platform and the
59 ** platform's ability to provide a random value at that moment.
61 ** The intent of PR_GetRandomNoise() is to provide a "seed" value for a
62 ** another random number generator that may be suitable for
63 ** cryptographic operations. This implies that the random value
64 ** provided may not be, by itself, cryptographically secure. The value
65 ** generated by PR_GetRandomNoise() is at best, extremely difficult to
66 ** predict and is as non-deterministic as the underlying platfrom can
70 ** buf -- pointer to a caller supplied buffer to contain the
71 ** generated random number. buf must be at least as large as
72 ** is specified in the 'size' argument.
74 ** size -- the requested size of the generated random number
77 ** a random number provided in 'buf'.
80 ** PRSize value equal to the size of the random number actually
81 ** generated, or zero. The generated size may be less than the size
82 ** requested. A return value of zero means that PR_GetRandomNoise() is
83 ** not implemented on this platform, or there is no available noise
84 ** available to be returned at the time of the call.
87 ** Calls to PR_GetRandomNoise() may use a lot of CPU on some platforms.
88 ** Some platforms may block for up to a few seconds while they
89 ** accumulate some noise. Busy machines generate lots of noise, but
90 ** care is advised when using PR_GetRandomNoise() frequently in your
94 ** Parts of the model dependent implementation for PR_GetRandomNoise()
95 ** were taken in whole or part from code previously in Netscape's NSS
99 NSPR_API(PRSize) PR_GetRandomNoise(
106 #endif /* prrng_h___ */