1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
=pod
=head1 NAME
bio - I/O abstraction
=head1 SYNOPSIS
#include <openssl/bio.h>
TBA
=head1 DESCRIPTION
A BIO is an I/O abstraction, it hides many of the underlying I/O
details from an application. If an application uses a BIO for its
I/O it can transparently handle SSL connections, unencrypted network
connections and file I/O.
There are two type of BIO, a source/sink BIO and a filter BIO.
As its name implies a source/sink BIO is a source and/or sink of data,
examples include a socket BIO and a file BIO.
A filter BIO takes data from one BIO and passes it through to
another, or the application. The data may be left unmodified (for
example a message digest BIO) or translated (for example an
encryption BIO). The effect of a filter BIO may change according
to the I/O operation it is performing: for example an encryption
BIO will encrypt data if it is being written to and decrypt data
if it is being read from.
BIOs can be joined together to form a chain (a single BIO is a chain
with one component). A chain normally consist of one source/sink
BIO and one or more filter BIOs. Data read from or written to the
first BIO then traverses the chain to the end (normally a source/sink
BIO).
=head1 SEE ALSO
L<BIO_ctrl(3)|BIO_ctrl(3)>,
L<BIO_f_base64(3)|BIO_f_base64(3)>, L<BIO_f_buffer(3)|BIO_f_buffer(3)>,
L<BIO_f_cipher(3)|BIO_f_cipher(3)>, L<BIO_f_md(3)|BIO_f_md(3)>,
L<BIO_f_null(3)|BIO_f_null(3)>, L<BIO_f_ssl(3)|BIO_f_ssl(3)>,
L<BIO_find_type(3)|BIO_find_type(3)>, L<BIO_new(3)|BIO_new(3)>,
L<BIO_new_bio_pair(3)|BIO_new_bio_pair(3)>,
L<BIO_push(3)|BIO_push(3)>, L<BIO_read(3)|BIO_read(3)>,
L<BIO_s_accept(3)|BIO_s_accept(3)>, L<BIO_s_bio(3)|BIO_s_bio(3)>,
L<BIO_s_connect(3)|BIO_s_connect(3)>, L<BIO_s_fd(3)|BIO_s_fd(3)>,
L<BIO_s_file(3)|BIO_s_file(3)>, L<BIO_s_mem(3)|BIO_s_mem(3)>,
L<BIO_s_null(3)|BIO_s_null(3)>, L<BIO_s_socket(3)|BIO_s_socket(3)>,
L<BIO_set_callback(3)|BIO_set_callback(3)>,
L<BIO_should_retry(3)|BIO_should_retry(3)>
|
