static double
constant(char* name)
{
    errno = 0;
    switch (*name) {
    case 'A':
	if (strEQ(name, "AT_MD5_WITH_RSA_ENCRYPTION"))
#ifdef SSL_AT_MD5_WITH_RSA_ENCRYPTION
	    return SSL_AT_MD5_WITH_RSA_ENCRYPTION;
#else
	    goto not_there;
#endif
	break;
      /* Snip similar for B..Z */
    case '_':
	if (strEQ(name, "_TEST_INVALID_CONSTANT"))
		goto not_there;
    }
    errno = EINVAL;
    return 0;

not_there:
    errno = ENOENT;
    return 0;
}