int ngx_posix_aio_process_events(ngx_log_t *log) { unmask signal listen via SIGIO; /* BUG: SIGIO can be delivered before aio_*() */ aio_suspend()/aiowait()/aio_waitcomplete() with timeout mask signal if (ngx_socket_errno == NGX_EINTR) look listen select()/accept() nb listen sockets else aio } int ngx_posix_aio_process_events(ngx_log_t *log) { unmask signal /* BUG: AIO signal can be delivered before select() */ select(listen); mask signal if (ngx_socket_errno == NGX_EINTR) look ready array } void aio_sig_handler(int signo, siginfo_t *siginfo, void *context) { push siginfo->si_value.sival_ptr }