Fixed portability issues with union sigval. AIO support in nginx was originally developed against FreeBSD versions 4-6, where the sival_ptr field was named as sigval_ptr (seemingly by mistake[1]), which made nginx use the only name available then. The standard-complaint name was restored in 2005 (first appeared in FreeBSD 7.0, 2008), retaining compatibility with previous versions[2][3]. In DragonFly, similar changes were committed in 2009[4], with backward compatibility recently removed[5]. The change switches to the standard name, retaining compatibility with old FreeBSD versions. [1] https://svnweb.freebsd.org/changeset/base/48621 [2] https://svnweb.freebsd.org/changeset/base/152029 [3] https://svnweb.freebsd.org/changeset/base/174003 [4] https://gitweb.dragonflybsd.org/dragonfly.git/commit/3693401 [5] https://gitweb.dragonflybsd.org/dragonfly.git/commit/7875042

/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_CHANNEL_H_INCLUDED_
#define _NGX_CHANNEL_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>


typedef struct {
    ngx_uint_t  command;
    ngx_pid_t   pid;
    ngx_int_t   slot;
    ngx_fd_t    fd;
} ngx_channel_t;


ngx_int_t ngx_write_channel(ngx_socket_t s, ngx_channel_t *ch, size_t size,
    ngx_log_t *log);
ngx_int_t ngx_read_channel(ngx_socket_t s, ngx_channel_t *ch, size_t size,
    ngx_log_t *log);
ngx_int_t ngx_add_channel_event(ngx_cycle_t *cycle, ngx_fd_t fd,
    ngx_int_t event, ngx_event_handler_pt handler);
void ngx_close_channel(ngx_fd_t *fd, ngx_log_t *log);


#endif /* _NGX_CHANNEL_H_INCLUDED_ */