1=pod
2
3=head1 NAME
4
5BN_zero, BN_one, BN_value_one, BN_set_word, BN_get_word - BIGNUM assignment
6operations
7
8=head1 SYNOPSIS
9
10 #include <openssl/bn.h>
11
12 int BN_zero(BIGNUM *a);
13 int BN_one(BIGNUM *a);
14
15 const BIGNUM *BN_value_one(void);
16
17 int BN_set_word(BIGNUM *a, unsigned long w);
18 unsigned long BN_get_word(BIGNUM *a);
19
20=head1 DESCRIPTION
21
22BN_zero(), BN_one() and BN_set_word() set B<a> to the values 0, 1 and
23B<w> respectively.  BN_zero() and BN_one() are macros.
24
25BN_value_one() returns a B<BIGNUM> constant of value 1. This constant
26is useful for use in comparisons and assignment.
27
28BN_get_word() returns B<a>, if it can be represented as an unsigned
29long.
30
31=head1 RETURN VALUES
32
33BN_get_word() returns the value B<a>, and 0xffffffffL if B<a> cannot
34be represented as an unsigned long.
35
36BN_zero(), BN_one() and BN_set_word() return 1 on success, 0 otherwise.
37BN_value_one() returns the constant.
38
39=head1 BUGS
40
41Someone might change the constant.
42
43If a B<BIGNUM> is equal to 0xffffffffL it can be represented as an
44unsigned long but this value is also returned on error.
45
46=head1 SEE ALSO
47
48L<bn(3)|bn(3)>, L<BN_bn2bin(3)|BN_bn2bin(3)>
49
50=head1 HISTORY
51
52BN_zero(), BN_one() and BN_set_word() are available in all versions of
53SSLeay and OpenSSL. BN_value_one() and BN_get_word() were added in
54SSLeay 0.8.
55
56BN_value_one() was changed to return a true const BIGNUM * in OpenSSL
570.9.7.
58
59=cut
60