harvey/sys/man/2/genrandom

.TH GENRANDOM 2
.SH NAME
genrandom, prng \- random number generation
.SH SYNOPSIS
.B #include <u.h>
.br
.B #include <libc.h>
.br
.B #include <mp.h>
.br
.B #include <libsec.h>
.PP
.B
void	genrandom(uchar *buf, int nbytes)
.PP
.B
void	prng(uchar *buf, int nbytes)
.SH DESCRIPTION
.PP
Most security software requires a source of random or, at the
very least, unguessable numbers.
.PP
.I Genrandom
fills a buffer with bytes from the X9.17 pseudo-random
number generator.  The X9.17 generator is seeded by 24
truly random bytes read from
.BR /dev/random .
.PP
.I Prng
uses the native
.IR rand (2)
pseudo-random number generator to fill the buffer.  Used with
.IR srand ,
this function can produce a reproducible stream of pseudo random
numbers useful in testing.
.PP
Both functions may be passed to
.I mprand
(see
.IR mp (2)).
.SH SOURCE
.B /sys/src/libsec
.SH SEE ALSO
.IR mp (2)