=pod

=head1 NAME

BN_cmp, BN_ucmp, BN_is_zero, BN_is_one, BN_is_word, BN_abs_is_word, BN_is_odd - BIGNUM comparison and test functions

=head1 SYNOPSIS

 #include <openssl/bn.h>

 int BN_cmp(const BIGNUM *a, const BIGNUM *b);
 int BN_ucmp(const BIGNUM *a, const BIGNUM *b);

 int BN_is_zero(const BIGNUM *a);
 int BN_is_one(const BIGNUM *a);
 int BN_is_word(const BIGNUM *a, const BN_ULONG w);
 int BN_abs_is_word(const BIGNUM *a, const BN_ULONG w);
 int BN_is_odd(const BIGNUM *a);

=head1 DESCRIPTION

BN_cmp() compares the numbers I<a> and I<b>. BN_ucmp() compares their
absolute values.

BN_is_zero(), BN_is_one(), BN_is_word() and BN_abs_is_word() test if
I<a> equals 0, 1, I<w>, or E<verbar>I<w>E<verbar> respectively.
BN_is_odd() tests if I<a> is odd.

=head1 RETURN VALUES

BN_cmp() returns -1 if I<a> E<lt> I<b>, 0 if I<a> == I<b> and 1 if
I<a> E<gt> I<b>. BN_ucmp() is the same using the absolute values
of I<a> and I<b>.

BN_is_zero(), BN_is_one() BN_is_word(), BN_abs_is_word() and
BN_is_odd() return 1 if the condition is true, 0 otherwise.

=head1 HISTORY

Prior to OpenSSL 1.1.0, BN_is_zero(), BN_is_one(), BN_is_word(),
BN_abs_is_word() and BN_is_odd() were macros.

=head1 COPYRIGHT

Copyright 2000-2021 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the OpenSSL license (the "License").  You may not use
this file except in compliance with the License.  You can obtain a copy
in the file LICENSE in the source distribution or at
L<https://www.openssl.org/source/license.html>.

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