note that SSL_library_init() is not reentrant
[openssl.git] / doc / ssl / SSL_library_init.pod
1 =pod
2
3 =head1 NAME
4
5 SSL_library_init, OpenSSL_add_ssl_algorithms, SSLeay_add_ssl_algorithms
6 - initialize SSL library by registering algorithms
7
8 =head1 SYNOPSIS
9
10  #include <openssl/ssl.h>
11
12  int SSL_library_init(void);
13  #define OpenSSL_add_ssl_algorithms()    SSL_library_init()
14  #define SSLeay_add_ssl_algorithms()     SSL_library_init()
15
16 =head1 DESCRIPTION
17
18 SSL_library_init() registers the available ciphers and digests.
19
20 OpenSSL_add_ssl_algorithms() and SSLeay_add_ssl_algorithms() are synonyms
21 for SSL_library_init().
22
23 =head1 NOTES
24
25 SSL_library_init() must be called before any other action takes place.
26 SSL_library_init() is not reentrant. 
27
28 =head1 WARNING
29
30 SSL_library_init() only registers ciphers. Another important initialization
31 is the seeding of the PRNG (Pseudo Random Number Generator), which has to
32 be performed separately.
33
34 =head1 EXAMPLES
35
36 A typical TLS/SSL application will start with the library initialization,
37 will provide readable error messages and will seed the PRNG.
38
39  SSL_load_error_strings();                /* readable error messages */
40  SSL_library_init();                      /* initialize library */
41  actions_to_seed_PRNG(); 
42
43 =head1 RETURN VALUES
44
45 SSL_library_init() always returns "1", so it is safe to discard the return
46 value.
47
48 =head1 SEE ALSO
49
50 L<ssl(3)|ssl(3)>, L<SSL_load_error_strings(3)|SSL_load_error_strings(3)>,
51 L<RAND_add(3)|RAND_add(3)>
52
53 =cut