BN_zero(3)							      OpenSSL								BN_zero(3)

NAME

       BN_zero, BN_one, BN_value_one, BN_set_word, BN_get_word - BIGNUM assignment operations

SYNOPSIS

	#include <openssl/bn.h>

	int BN_zero(BIGNUM *a);
	int BN_one(BIGNUM *a);

	const BIGNUM *BN_value_one(void);

	int BN_set_word(BIGNUM *a, unsigned long w);
	unsigned long BN_get_word(BIGNUM *a);

DESCRIPTION

       BN_zero(), BN_one() and BN_set_word() set a to the values 0, 1 and w respectively.  BN_zero() and BN_one() are macros.

       BN_value_one() returns a BIGNUM constant of value 1. This constant is useful for use in comparisons and assignment.

       BN_get_word() returns a, if it can be represented as an unsigned long.

RETURN VALUES

       BN_get_word() returns the value a, and 0xffffffffL if a cannot be represented as an unsigned long.

       BN_zero(), BN_one() and BN_set_word() return 1 on success, 0 otherwise.	BN_value_one() returns the constant.

BUGS

       Someone might change the constant.

       If a BIGNUM is equal to 0xffffffffL it can be represented as an unsigned long but this value is also returned on error.

SEE ALSO

       bn(3), BN_bn2bin(3)

HISTORY

       BN_zero(), BN_one() and BN_set_word() are available in all versions of SSLeay and OpenSSL. BN_value_one() and BN_get_word() were added in
       SSLeay 0.8.

       BN_value_one() was changed to return a true const BIGNUM * in OpenSSL 0.9.7.

0.9.7a								    2002-07-18								BN_zero(3)