NAME

       OPENSSL_config, OPENSSL_no_config - simple OpenSSL configuration functions

SYNOPSIS

        #include <openssl/conf.h>

        void OPENSSL_config(const char *config_name);
        void OPENSSL_no_config(void);

DESCRIPTION

       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.

NOTES

       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 threads).

       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 configuration file.

       Applications should free up configuration at application closedown by calling CONF_modules_free().

RETURN VALUES

       Neither OPENSSL_config() nor OPENSSL_no_config() return a value.

SEE ALSO

       conf(5), CONF_load_modules_file(3), CONF_modules_free(3)

HISTORY

       OPENSSL_config() and OPENSSL_no_config() first appeared in OpenSSL 0.9.7

1.0.2g                                             2016-03-01                               OPENSSL_config(3SSL)