/usr/man2/cat.3/BN_zero.3.Z(/usr/man2/cat.3/BN_zero.3.Z)

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, BN_ULONG w);
        BN_ULONG BN_get_word(BIGNUM *a);

DESCRIPTION

       BN_ULONG is a macro that will be an unsigned integral type optimied for
       the most efficient implementation on the local platform.

       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 a BN_ULONG.

RETURN VALUES

       BN_get_word() returns the value a, or all-bits-set if a cannot be rep-
       resented as a BN_ULONG.

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

BUGS

       If a BIGNUM is equal to the value of all-bits-set, it will collide with
       the error condition returned by BN_get_word() which uses that as an
       error value.

       BN_ULONG should probably be a typedef.

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.

1.0.2t                            2019-09-10                        BN_zero(3)
See also BN_get_word(3)
See also BN_one(3)
See also BN_set_word(3)
See also BN_value_one(3)