5 OPENSSL_config, OPENSSL_no_config - simple OpenSSL configuration functions
9 #include <openssl/conf.h>
11 void OPENSSL_config(const char *config_name);
12 void OPENSSL_no_config(void);
16 OPENSSL_config() configures OpenSSL using the standard B<openssl.cnf>
17 configuration file name using B<config_name>. If B<config_name> is NULL then
18 the file specified in the environment variable B<OPENSSL_CONF> will be used,
19 and if that is not set then a system default location is used.
20 Errors are silently ignored.
21 Multiple calls have no effect.
23 OPENSSL_no_config() disables configuration. If called before OPENSSL_config()
24 no configuration takes place.
28 The OPENSSL_config() function is designed to be a very simple "call it and
30 It is however B<much> better than nothing. Applications which need finer
31 control over their configuration functionality should use the configuration
32 functions such as CONF_modules_load() directly. This function is deprecated
33 and its use should be avoided.
34 Applications should instead call CONF_modules_load() during
35 initialization (that is before starting any threads).
37 There are several reasons why calling the OpenSSL configuration routines is
38 advisable. For example new ENGINE functionality was added to OpenSSL 0.9.7.
39 In OpenSSL 0.9.7 control functions can be supported by ENGINEs, this can be
40 used (among other things) to load dynamic ENGINEs from shared libraries (DSOs).
41 However very few applications currently support the control interface and so
42 very few can load and use dynamic ENGINEs. Equally in future more sophisticated
43 ENGINEs will require certain control operations to customize them. If an
44 application calls OPENSSL_config() it doesn't need to know or care about
45 ENGINE control operations because they can be performed by editing a
48 Applications should free up configuration at application closedown by calling
53 The OPENSSL_config() function is designed to be a very simple "call it and
54 forget it" function. As a result its behaviour is somewhat limited. It ignores
55 all errors silently and it can only load from the standard configuration file
58 It is however B<much> better than nothing. Applications which need finer
59 control over their configuration functionality should use the configuration
60 functions such as CONF_load_modules() directly.
64 Neither OPENSSL_config() nor OPENSSL_no_config() return a value.
68 L<conf(5)|conf(5)>, L<CONF_load_modules_file(3)|CONF_load_modules_file(3)>,
69 L<CONF_modules_free(3)|CONF_modules_free(3)>
73 OPENSSL_config() and OPENSSL_no_config() first appeared in OpenSSL 0.9.7