xref: /freebsd/crypto/openssl/doc/man3/BIO_new.pod (revision bfcc09ddd422c95a1a2e4e794b63ee54c4902398)
1=pod
2
3=head1 NAME
4
5BIO_new, BIO_up_ref, BIO_free, BIO_vfree, BIO_free_all
6- BIO allocation and freeing functions
7
8=head1 SYNOPSIS
9
10 #include <openssl/bio.h>
11
12 BIO *  BIO_new(const BIO_METHOD *type);
13 int    BIO_up_ref(BIO *a);
14 int    BIO_free(BIO *a);
15 void   BIO_vfree(BIO *a);
16 void   BIO_free_all(BIO *a);
17
18=head1 DESCRIPTION
19
20The BIO_new() function returns a new BIO using method B<type>.
21
22BIO_up_ref() increments the reference count associated with the BIO object.
23
24BIO_free() frees up a single BIO, BIO_vfree() also frees up a single BIO
25but it does not return a value.
26If B<a> is NULL nothing is done.
27Calling BIO_free() may also have some effect
28on the underlying I/O structure, for example it may close the file being
29referred to under certain circumstances. For more details see the individual
30BIO_METHOD descriptions.
31
32BIO_free_all() frees up an entire BIO chain, it does not halt if an error
33occurs freeing up an individual BIO in the chain.
34If B<a> is NULL nothing is done.
35
36=head1 RETURN VALUES
37
38BIO_new() returns a newly created BIO or NULL if the call fails.
39
40BIO_up_ref() and BIO_free() return 1 for success and 0 for failure.
41
42BIO_free_all() and BIO_vfree() do not return values.
43
44=head1 NOTES
45
46If BIO_free() is called on a BIO chain it will only free one BIO resulting
47in a memory leak.
48
49Calling BIO_free_all() on a single BIO has the same effect as calling BIO_free()
50on it other than the discarded return value.
51
52=head1 HISTORY
53
54BIO_set() was removed in OpenSSL 1.1.0 as BIO type is now opaque.
55
56=head1 EXAMPLES
57
58Create a memory BIO:
59
60 BIO *mem = BIO_new(BIO_s_mem());
61
62=head1 COPYRIGHT
63
64Copyright 2000-2019 The OpenSSL Project Authors. All Rights Reserved.
65
66Licensed under the OpenSSL license (the "License").  You may not use
67this file except in compliance with the License.  You can obtain a copy
68in the file LICENSE in the source distribution or at
69L<https://www.openssl.org/source/license.html>.
70
71=cut
72