1BN_SET_BIT(3)                       OpenSSL                      BN_SET_BIT(3)
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NAME

6       BN_set_bit, BN_clear_bit, BN_is_bit_set, BN_mask_bits, BN_lshift,
7       BN_lshift1, BN_rshift, BN_rshift1 - bit operations on BIGNUMs
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SYNOPSIS

10        #include <openssl/bn.h>
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12        int BN_set_bit(BIGNUM *a, int n);
13        int BN_clear_bit(BIGNUM *a, int n);
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15        int BN_is_bit_set(const BIGNUM *a, int n);
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17        int BN_mask_bits(BIGNUM *a, int n);
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19        int BN_lshift(BIGNUM *r, const BIGNUM *a, int n);
20        int BN_lshift1(BIGNUM *r, BIGNUM *a);
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22        int BN_rshift(BIGNUM *r, BIGNUM *a, int n);
23        int BN_rshift1(BIGNUM *r, BIGNUM *a);
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DESCRIPTION

26       BN_set_bit() sets bit n in a to 1 ("a|=(1<<n)"). The number is expanded
27       if necessary.
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29       BN_clear_bit() sets bit n in a to 0 ("a&=~(1<<n)"). An error occurs if
30       a is shorter than n bits.
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32       BN_is_bit_set() tests if bit n in a is set.
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34       BN_mask_bits() truncates a to an n bit number ("a&=~((~0)<<n)").  An
35       error occurs if a already is shorter than n bits.
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37       BN_lshift() shifts a left by n bits and places the result in r
38       ("r=a*2^n"). Note that n must be nonnegative. BN_lshift1() shifts a
39       left by one and places the result in r ("r=2*a").
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41       BN_rshift() shifts a right by n bits and places the result in r
42       ("r=a/2^n"). Note that n must be nonnegative. BN_rshift1() shifts a
43       right by one and places the result in r ("r=a/2").
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45       For the shift functions, r and a may be the same variable.
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RETURN VALUES

48       BN_is_bit_set() returns 1 if the bit is set, 0 otherwise.
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50       All other functions return 1 for success, 0 on error. The error codes
51       can be obtained by ERR_get_error(3).
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SEE ALSO

54       BN_num_bytes(3), BN_add(3)
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57       Copyright 2000-2020 The OpenSSL Project Authors. All Rights Reserved.
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59       Licensed under the OpenSSL license (the "License").  You may not use
60       this file except in compliance with the License.  You can obtain a copy
61       in the file LICENSE in the source distribution or at
62       <https://www.openssl.org/source/license.html>.
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661.1.1q                            2023-07-20                     BN_SET_BIT(3)
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