@deftypefun {int} {gnutls_x509_trust_list_add_trust_file} (gnutls_x509_trust_list_t @var{list}, const char * @var{ca_file}, const char * @var{crl_file}, gnutls_x509_crt_fmt_t @var{type}, unsigned int @var{tl_flags}, unsigned int @var{tl_vflags}) @var{list}: The list @var{ca_file}: A file containing a list of CAs (optional) @var{crl_file}: A file containing a list of CRLs (optional) @var{type}: The format of the certificates @var{tl_flags}: flags from @code{gnutls_trust_list_flags_t} @var{tl_vflags}: gnutls_certificate_verify_flags if flags specifies GNUTLS_TL_VERIFY_CRL This function will add the given certificate authorities to the trusted list. PKCS @code{11} URLs are also accepted, instead of files, by this function. A PKCS @code{11} URL implies a trust database (a specially marked module in p11-kit); the URL "pkcs11:" implies all trust databases in the system. Only a single URL specifying trust databases can be set; they cannot be stacked with multiple calls. @strong{Returns:} The number of added elements is returned. @strong{Since:} 3.1 @end deftypefun