DragonFly On-Line Manual Pages
OPENSSL_config(3) OpenSSL OPENSSL_config(3)
OPENSSL_config, OPENSSL_no_config - simple OpenSSL configuration
void OPENSSL_config(const char *config_name);
OPENSSL_config() configures OpenSSL using the standard openssl.cnf
configuration file name using config_name. If config_name is NULL then
the file specified in the environment variable OPENSSL_CONF will be
used, and if that is not set then a system default location is used.
Errors are silently ignored. Multiple calls have no effect.
OPENSSL_no_config() disables configuration. If called before
OPENSSL_config() no configuration takes place.
The OPENSSL_config() function is designed to be a very simple "call it
and forget it" function. It is however much better than nothing.
Applications which need finer control over their configuration
functionality should use the configuration functions such as
CONF_modules_load() directly. This function is deprecated and its use
should be avoided. Applications should instead call
CONF_modules_load() during initialization (that is before starting any
There are several reasons why calling the OpenSSL configuration
routines is advisable. For example new ENGINE functionality was added
to OpenSSL 0.9.7. In OpenSSL 0.9.7 control functions can be supported
by ENGINEs, this can be used (among other things) to load dynamic
ENGINEs from shared libraries (DSOs). However very few applications
currently support the control interface and so very few can load and
use dynamic ENGINEs. Equally in future more sophisticated ENGINEs will
require certain control operations to customize them. If an application
calls OPENSSL_config() it doesn't need to know or care about ENGINE
control operations because they can be performed by editing a
Applications should free up configuration at application closedown by
Neither OPENSSL_config() nor OPENSSL_no_config() return a value.
conf(5), CONF_load_modules_file(3), CONF_modules_free(3)
OPENSSL_config() and OPENSSL_no_config() first appeared in OpenSSL
1.0.2h 2016-05-03 OPENSSL_config(3)