1BN_ZERO(3ossl)                      OpenSSL                     BN_ZERO(3ossl)
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NAME

6       BN_zero, BN_one, BN_value_one, BN_set_word, BN_get_word - BIGNUM
7       assignment operations
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SYNOPSIS

10        #include <openssl/bn.h>
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12        void BN_zero(BIGNUM *a);
13        int BN_one(BIGNUM *a);
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15        const BIGNUM *BN_value_one(void);
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17        int BN_set_word(BIGNUM *a, BN_ULONG w);
18        unsigned BN_ULONG BN_get_word(BIGNUM *a);
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DESCRIPTION

21       BN_ULONG is a macro that will be an unsigned integral type optimized
22       for the most efficient implementation on the local platform.
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24       BN_zero(), BN_one() and BN_set_word() set a to the values 0, 1 and w
25       respectively.  BN_zero() and BN_one() are macros.
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27       BN_value_one() returns a BIGNUM constant of value 1. This constant is
28       useful for use in comparisons and assignment.
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30       BN_get_word() returns a, if it can be represented as a BN_ULONG.
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RETURN VALUES

33       BN_get_word() returns the value a, or all-bits-set if a cannot be
34       represented as a single integer.
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36       BN_one() and BN_set_word() return 1 on success, 0 otherwise.
37       BN_value_one() returns the constant.  BN_zero() never fails and returns
38       no value.
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BUGS

41       If a BIGNUM is equal to the value of all-bits-set, it will collide with
42       the error condition returned by BN_get_word() which uses that as an
43       error value.
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45       BN_ULONG should probably be a typedef.
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SEE ALSO

48       BN_bn2bin(3)
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HISTORY

51       In OpenSSL 0.9.8, BN_zero() was changed to not return a value; previous
52       versions returned an int.
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55       Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
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57       Licensed under the Apache License 2.0 (the "License").  You may not use
58       this file except in compliance with the License.  You can obtain a copy
59       in the file LICENSE in the source distribution or at
60       <https://www.openssl.org/source/license.html>.
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643.1.1                             2023-08-31                    BN_ZERO(3ossl)
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