un.h

cygwin, 著名的在win32下模拟unix操作系统的东东

/* sys/un.h

   Copyright 1999, 2001 Red Hat, Inc.

This file is part of Cygwin.

This software is a copyrighted work licensed under the terms of the
Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
details. */

#ifndef _SYS_UN_H
#define _SYS_UN_H

/* POSIX requires only at least 100 bytes */
#define UNIX_PATH_LEN   108

struct sockaddr_un {
  unsigned short sun_family;              /* address family AF_LOCAL/AF_UNIX */
  char	         sun_path[UNIX_PATH_LEN]; /* 108 bytes of socket address     */
};

/* Evaluates the actual length of `sockaddr_un' structure. */
#define SUN_LEN(p) ((size_t)(((struct sockaddr_un *) NULL)->sun_path) \
		   + strlen ((p)->sun_path))

#endif