bool f_headers_sent(VRefParam file /* = null */, VRefParam line /* = null */) {
    Transport *transport = g_context->getTransport();
    if (transport) {
        file = String(transport->getFirstHeaderFile());
        line = transport->getFirstHeaderLine();
        return transport->headersSent();
    }
    return false;
}
bool HHVM_FUNCTION(headers_sent, VRefParam file /* = null */,
                   VRefParam line /* = null */) {
    Transport *transport = g_context->getTransport();
    if (transport) {
        file = String(transport->getFirstHeaderFile());
        line = transport->getFirstHeaderLine();
        return transport->headersSent();
    } else {
        return g_context->getStdoutBytesWritten() > 0;
    }
    return false;
}