BN_new.pod revision 325337 
1=pod
2
3=head1 NAME
4
5BN_new, BN_init, BN_clear, BN_free, BN_clear_free - allocate and free BIGNUMs
6
7=head1 SYNOPSIS
8
9 #include <openssl/bn.h>
10
11 BIGNUM *BN_new(void);
12
13 void BN_init(BIGNUM *);
14
15 void BN_clear(BIGNUM *a);
16
17 void BN_free(BIGNUM *a);
18
19 void BN_clear_free(BIGNUM *a);
20
21=head1 DESCRIPTION
22
23BN_new() allocates and initializes a B<BIGNUM> structure. BN_init()
24initializes an existing uninitialized B<BIGNUM>.
25
26BN_clear() is used to destroy sensitive data such as keys when they
27are no longer needed. It erases the memory used by B<a> and sets it
28to the value 0.
29
30BN_free() frees the components of the B<BIGNUM>, and if it was created
31by BN_new(), also the structure itself. BN_clear_free() additionally
32overwrites the data before the memory is returned to the system.
33If B<a> is NULL, nothing is done.
34
35=head1 RETURN VALUES
36
37BN_new() returns a pointer to the B<BIGNUM> initialised to the value 0.
38If the allocation fails,
39it returns B<NULL> and sets an error code that can be obtained
40by L<ERR_get_error(3)|ERR_get_error(3)>.
41
42BN_init(), BN_clear(), BN_free() and BN_clear_free() have no return
43values.
44
45=head1 SEE ALSO
46
47L<bn(3)|bn(3)>, L<ERR_get_error(3)|ERR_get_error(3)>
48
49=head1 HISTORY
50
51BN_new(), BN_clear(), BN_free() and BN_clear_free() are available in
52all versions on SSLeay and OpenSSL.  BN_init() was added in SSLeay
530.9.1b.
54
55=cut
56