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RAND_bytes(3)			    OpenSSL			 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. An error occurs if the PRNG	has not	been seeded with enough
       randomness to ensure an unpredictable byte sequence.

       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.

       The contents of buf is mixed into the entropy pool before retrieving
       the new pseudo-random bytes unless disabled at compile time (see	FAQ).

RETURN VALUES
       RAND_bytes() returns 1 on success, 0 otherwise. The error code can be
       obtained	by ERR_get_error(3). 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.

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.

1.0.1e				  2013-02-11			 RAND_bytes(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | HISTORY

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