ERR_FNS           376 extra_lib/include/openssl/err.h const ERR_FNS *ERR_get_implementation(void);
ERR_FNS           379 extra_lib/include/openssl/err.h int ERR_set_implementation(const ERR_FNS *fns);
ERR_FNS           167 extra_lib/include/openssl/ossl_typ.h typedef struct st_ERR_FNS ERR_FNS;