[Lucas Malor]

It could be simply that it's more resource consuming to turn the pixel to black. It seems to me that in night mode Kobo is a bit more slow.

Anyway, what does exaclt this piece of code?

    while(1)
    {
        int err = epoll_wait(epollFD, &readEvent, 1, -1);
        if(err > 0)
        {
            int bytesRead = read(fd, &input, sizeof(input));
            
            if(bytesRead == 0) //writing application left the pipe -> reopen
            {
                close(fd);
                fd = open(ctlPipe, O_NONBLOCK);
                readEvent.data.fd = fd;
                epoll_ctl(epollFD, EPOLL_CTL_ADD, fd, &readEvent);
                continue;
            }