X509_PURPOSE_get_by_sname
i = X509_PURPOSE_get_by_sname(opt_arg());
if ((purpose_id = X509_PURPOSE_get_by_sname(SN_cmKGA)) < 0) {
idx = X509_PURPOSE_get_by_sname(sname);
int X509_PURPOSE_get_by_sname(const char *sname);
&& TEST_int_eq(X509_PURPOSE_get_by_sname(SN), -1)
&& TEST_int_ne((idx = X509_PURPOSE_get_by_sname(SN)), -1)
&& TEST_int_eq(X509_PURPOSE_get_by_sname(SN), idx)