NGX_CLEAR_EVENT   387 event/ngx_event.h #define NGX_CLEAR_EVENT    EV_CLEAR
NGX_CLEAR_EVENT   408 event/ngx_event.h #define NGX_CLEAR_EVENT    EPOLLET
NGX_CLEAR_EVENT   443 event/ngx_event.h #define NGX_CLEAR_EVENT    0    /* dummy declaration */