[libmicrohttpd] how to make MHD use poll instead of select

[Ken Zangelin]

Hi,

    I am unsuccessfully trying to get MHD use poll instead of select.

According to the documentation, MHD_USE_POLL (64) should do the trick, 
however, I still see only calls to select(), after calling 
MHD_start_daemon like this:


      int serverMode = MHD_USE_THREAD_PER_CONNECTION | MHD_USE_POLL;

      mhdDaemon = MHD_start_daemon(serverMode,
                                   htons(port),
                                   NULL,
                                   NULL,
connectionTreat,                     NULL,
MHD_OPTION_CONNECTION_MEMORY_LIMIT,  memoryLimit,
MHD_OPTION_CONNECTION_LIMIT,         maxConns,
MHD_OPTION_THREAD_POOL_SIZE,         threadPoolSize,
MHD_OPTION_SOCK_ADDR,                (struct sockaddr*) &sad,
MHD_OPTION_NOTIFY_COMPLETED,         requestCompleted, NULL,
                                   MHD_OPTION_END);

I've tried with a few more combinations (depending on the CLI args for 
our server), like:

    int serverMode = MHD_USE_SELECT_INTERNALLY | MHD_USE_POLL;  // 
MHD_USE_POLL_INTERNALLY

And also changing poll for epoll:

    int serverMode = MHD_USE_SELECT_INTERNALLY | MHD_USE_EPOLL_LINUX_ONLY;


However, no calls to poll according to strace, just select ...

I'm on CentOS 6.5 and the version of MHD (not too new), according to 
microhttpd.h, is:

    /**
     * Current version of the library.
     * 0x01093001 = 1.9.30-1.
     */
    #define MHD_VERSION 0x00093300

[ A bit strange btw ... MHD_VERSION says 0.9.33-0 while the comment says 
1.9.30-1 ... ]

What am I doing wrong? Why isn't poll used?


Thanks,

/Ken Z