static void pty_chr_update_read_handler_locked(CharDriverState *chr)
{
    PtyCharDriver *s = chr->opaque;
    GPollFD pfd;
    int rc;
    QIOChannelFile *fioc = QIO_CHANNEL_FILE(s->ioc);

    pfd.fd = fioc->fd;
    pfd.events = G_IO_OUT;
    pfd.revents = 0;
    do {
        rc = g_poll(&pfd, 1, 0);
    } while (rc == -1 && errno == EINTR);
    assert(rc >= 0);

    if (pfd.revents & G_IO_HUP) {
        pty_chr_state(chr, 0);
    } else {
        pty_chr_state(chr, 1);
    }
}
static void pty_chr_update_read_handler_locked(CharDriverState *chr)
{
    PtyCharDriver *s = chr->opaque;
    GPollFD pfd;
    int rc;
    QIOChannelFile *fioc = QIO_CHANNEL_FILE(s->ioc);

    pfd.fd = fioc->fd;
    pfd.events = G_IO_OUT;
    pfd.revents = 0;
    do {
        rc = g_poll(&pfd, 1, 0);
    } while (rc == -1 && errno == EINTR);
    assert(rc >= 0);

    if (pfd.revents & G_IO_HUP) {
        pty_chr_state(chr, 0);
    } else {
        pty_chr_state(chr, 1);
    }
}