=pod =head1 NAME RAND_bytes, RAND_pseudo_bytes - generate random data =head1 SYNOPSIS #include int RAND_bytes(unsigned char *buf, int num); int RAND_pseudo_bytes(unsigned char *buf, int num); =head1 DESCRIPTION RAND_bytes() puts B cryptographically strong pseudo-random bytes into B. An error occurs if the PRNG has not been seeded with enough randomness to ensure an unpredictable byte sequence. RAND_pseudo_bytes() puts B pseudo-random bytes into B. 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. The contents of B is mixed into the entropy pool before retrieving the new pseudo-random bytes unless disabled at compile time (see FAQ). =head1 RETURN VALUES RAND_bytes() returns 1 on success, 0 otherwise. The error code can be obtained by L. RAND_pseudo_bytes() returns 1 if the bytes generated are cryptographically strong, 0 otherwise. Both functions return -1 if they are not supported by the current RAND method. =head1 SEE ALSO L, L, L =head1 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. =cut