man3type/epoll_event.3type

   1 .\" Copyright (c) 2022 by Alejandro Colomar <alx@kernel.org>
   2 .\"
   3 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   4 .\"
   5 .\"
   6 .TH epoll_event 3type (date) "Linux man-pages (unreleased)"
   7 .SH NAME
   8 epoll_event, epoll_data, epoll_data_t
   9 \- epoll event
  10 .SH LIBRARY
  11 Standard C library
  12 .RI ( libc )
  13 .SH SYNOPSIS
  14 .EX
  15 .B #include <sys/epoll.h>
  16 .PP
  17 .B struct epoll_event {
  18 .BR "    uint32_t      events;" "  /* Epoll events */"
  19 .BR "    epoll_data_t  data;" "    /* User data variable */"
  20 .B };
  21 .PP
  22 .B union epoll_data {
  23 .B "    void     *ptr;"
  24 .B "    int       fd;"
  25 .B "    uint32_t  u32;"
  26 .B "    uint64_t  u64;"
  27 .B };
  28 .PP
  29 .B "typedef union epoll_data  epoll_data_t;"
  30 .EE
  31 .SH DESCRIPTION
  32 The
  33 .I epoll_event
  34 structure specifies data that the kernel should save and
  35 return when the corresponding file descriptor becomes ready.
  36 .SH STANDARDS
  37 This type is Linux-specific.
  38 .SH NOTES
  39 .SS C library/kernel differences
  40 The Linux kernel headers also provide this type,
  41 with a slightly different definition:
  42 .PP
  43 .in +4n
  44 .EX
  45 #include <linux/eventpoll.h>
  46
  47 struct epoll_event {
  48     __poll_t  events;
  49     __u64     data;
  50 };
  51 .EE
  52 .in
  53 .SH SEE ALSO
  54 .BR epoll_wait (2),
  55 .BR epoll_ctl (7)