recvfrom() never ending

#include <winsock.h>

    #define RECV_TIMEOUT 10	/* timeout in seconds */

    SOCKET sock;                        /* Socket descriptor -- int in UNIX */
    unsigned long nonblocking = 1;    /* Flag to make socket nonblocking */
    int timeout;

    /* Set the socket to nonblocking */
    /* fcntl(sock, F_SETFL,O_NONBLOCK|FASYNC) under UNIX */
    if (ioctlsocket(sock, FIONBIO, &nonblocking) != 0)
        DieWithError("ioctlsocket() failed");
...

    /* Receive a single datagram from the server */
    for (timeout=RECV_TIMEOUT; timeout > 0; timeout--)
    {
        /* recvfrom() returns -1 if error */
        if ((recvStringLen = recvfrom(sock, recvString, MAXRECVSTRING, 0, NULL, 0)) < 0)
        {
            if (WSAGetLastError() != WSAEWOULDBLOCK) 
              /* EWOULDBLOCK in UNIX */
                DieWithError("recvfrom() failed");
            else
            {
                printf("Still have not received packet...Waiting and then trying again\n");
                Sleep(1000);  /* Sleep for 1 second */
            }
        }
        else  /* have received datagram */
            break;
    }

    if (!timeout)
    {
        printf("Timed out.\n");
        exit(1);
    }

    /* process received datagram  */