gr_wait.c

来自「SIP 1.5.0源代码」· C语言 代码 · 共 54 行

/*
 * Program:	UNIX Grim PID Reaper -- wait() version
 *
 * Author:	Mark Crispin
 *		Networks and Distributed Computing
 *		Computing & Communications
 *		University of Washington
 *		Administration Building, AG-44
 *		Seattle, WA  98195
 *		Internet: [e-mail]
 *
 * Date:	30 November 1993
 * Last Edited:	9 October 1995
 *
 * Copyright 1995 by the University of Washington
 *
 *  Permission to use, copy, modify, and distribute this software and its
 * documentation for any purpose and without fee is hereby granted, provided
 * that the above copyright notice appears in all copies and that both the
 * above copyright notice and this permission notice appear in supporting
 * documentation, and that the name of the University of Washington not be
 * used in advertising or publicity pertaining to distribution of the software
 * without specific, written prior permission.  This software is made available
 * "as is", and
 * THE UNIVERSITY OF WASHINGTON DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED,
 * WITH REGARD TO THIS SOFTWARE, INCLUDING WITHOUT LIMITATION ALL IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, AND IN
 * NO EVENT SHALL THE UNIVERSITY OF WASHINGTON BE LIABLE FOR ANY SPECIAL,
 * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, TORT
 * (INCLUDING NEGLIGENCE) OR STRICT LIABILITY, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */
 
/* Grim PID reaper
 * Accepts: process ID
 *	    kill request flag
 *	    status return value
 */

void grim_pid_reap_status (int pid,int killreq,void *status)
{
  int r;
  if (killreq) {
    kill (pid,SIGHUP);		/* kill if not already dead */
    alarm (10);			/* in case we get hosed */
    while (((r = wait (NIL)) != pid) &&
	   ((r > 0) || ((errno != ECHILD) && (errno != EINTR))));
    alarm (0);			/* cancel the alarm */
  }
  else while (((r = wait (status)) != pid) && ((r > 0) || (errno != ECHILD)));
}