NSS_CK_SET_ATTRIBUTE_ITEM(cert_template, 0, &g_ck_class_cert);
nssToken_TraverseCertificates(  NSSToken *tok,  nssSession *sessionOpt,  PRStatus (*callback)(NSSCertificate *c, void *arg),  void *arg){    PRStatus nssrv;    /* this is really traversal - the template is all certs */    CK_ATTRIBUTE cert_template[] = {	{ CKA_CLASS, g_ck_class_cert.data, g_ck_class_cert.size }    };    CK_ULONG ctsize = sizeof(cert_template) / sizeof(cert_template[0]);    nssrv = nssToken_FindCertificatesByTemplate(tok, sessionOpt,                                                 cert_template, ctsize,                                                callback, arg);    return NULL; /* XXX */}