apr_pollset_poll

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apr_pollset_poll

APR_DECLARE(apr_status_t) apr_pollset_poll(apr_pollset_t *pollset,
                                           apr_interval_time_t timeout,
                                           apr_int32_t *num,
                                           const apr_pollfd_t **descriptors);

struct apr_pollset_t
{
    apr_pool_t *pool;
    apr_uint32_t nelts;
    apr_uint32_t nalloc;
    struct pollfd *pollset;
    apr_pollfd_t *query_set;
    apr_pollfd_t *result_set;
};

/** Used in apr_pollfd_t to determine what the apr_descriptor is */
typedef enum { 
    APR_NO_DESC,                /**< nothing here */
    APR_POLL_SOCKET,            /**< descriptor refers to a socket */
    APR_POLL_FILE,              /**< descriptor refers to a file */
    APR_POLL_LASTDESC           /**< descriptor is the last one in the list */
} apr_datatype_e ;

/** Union of either an APR file or socket. */
typedef union {
    apr_file_t *f;              /**< file */
    apr_socket_t *s;            /**< socket */
} apr_descriptor;

/** @see apr_pollfd_t */
typedef struct apr_pollfd_t apr_pollfd_t;

/** Poll descriptor set. */
struct apr_pollfd_t {
    apr_pool_t *p;              /**< associated pool */
    apr_datatype_e desc_type;   /**< descriptor type */
    apr_int16_t reqevents;      /**< requested events */
    apr_int16_t rtnevents;      /**< returned events */
    apr_descriptor desc;        /**< @see apr_descriptor */
    void *client_data;          /**< allows app to associate context */
};