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