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=head1 NAME

BN_rand - Generate pseudo-random number

=head1 SYNOPSIS

 #include <openssl/bn.h>

 int BN_rand(BIGNUM *rnd, int bits, int top, int bottom);

=head1 DESCRIPTION

BN_rand() generates a cryptographically strong pseudo-random number of
B<bits> bits in length and stores it in B<rnd>. If B<top> is true, the
two most significant bits of the number will be set to 1, so that the
product of two such random numbers will always have 2*B<bits> length.
If B<bottom> is true, the number will be odd.

The PRNG must be seeded prior to calling BN_rand().

=head1 RETURN VALUES

BN_rand() returns 1 on success, 0 on error.
The error codes can be obtained by ERR_get_error(3).

=head1 SEE ALSO

bn(3), err(3), rand(3), RAND_add(), RAND_bytes()

=head1 HISTORY

BN_rand() is available in all versions of SSLeay and OpenSSL.

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