static char *make_config_name()
{
    const char *t;
    size_t len;
    char *p;

    if ((t = getenv("OPENSSL_CONF")) != NULL)
        return BUF_strdup(t);

    t = X509_get_default_cert_area();
    len = strlen(t) + 1 + strlen(OPENSSL_CONF) + 1;
    p = app_malloc(len, "config filename buffer");
    strcpy(p, t);
#ifndef OPENSSL_SYS_VMS
    strcat(p, "/");
#endif
    strcat(p, OPENSSL_CONF);

    return p;
}