NGX_CLEAR_EVENT   340 src/event/ngx_event.h #define NGX_CLEAR_EVENT    EV_CLEAR
NGX_CLEAR_EVENT   361 src/event/ngx_event.h #define NGX_CLEAR_EVENT    EPOLLET
NGX_CLEAR_EVENT   396 src/event/ngx_event.h #define NGX_CLEAR_EVENT    0    /* dummy declaration */