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RAND_bytes(3) LibreSSL RAND_bytes(3)

NAME

RAND_bytes, RAND_pseudo_bytes - generate random data

SYNOPSIS


#include <openssl/rand.h>

int RAND_bytes(unsigned char *buf, int num);

int RAND_pseudo_bytes(unsigned char *buf, int num);

DESCRIPTION

RAND_bytes() puts num cryptographically strong pseudo-random bytes into buf.
RAND_pseudo_bytes() puts num pseudo-random bytes into buf. Pseudo-random byte sequences generated by RAND_pseudo_bytes() will be unique if they are of sufficient length, but are not necessarily unpredictable. They can be used for non-cryptographic purposes and for certain purposes in cryptographic protocols, but usually not for key generation etc.

RETURN VALUES

RAND_bytes() returns 1. RAND_pseudo_bytes() returns 1.

SEE ALSO

rand(3), ERR_get_error(3), RAND_add(3)

HISTORY

RAND_bytes() is available in all versions of SSLeay and OpenSSL. It has a return value since OpenSSL 0.9.5. RAND_pseudo_bytes() was added in OpenSSL 0.9.5.
2015-10-26 LibreSSL
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