/* print string at start of shared memory segment */

/* 21 Oct 1991 by Eric Grosse.  Copyright (c) 1991 by AT&T.
 * Permission to use, copy, modify, and distribute this software for any
 * purpose without fee is hereby granted, provided that this entire notice
 * is included in all copies of any software which is or includes a copy
 * or modification of this software and in all copies of the supporting
 * documentation for such software.
 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHORS NOR AT&T MAKE ANY
 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
 * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
 */
#include <stdio.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>


main(int argc, char **argv)
{
	char *shm;
	int n;
	if(argc!=2){
		fprintf(stderr,"usage: shmid n\n");
		exit(1);
	}
	n = atoi(argv[1]);
	shm = (char*)shmat(n, 0, SHM_RDONLY);
	if (shm == (char *)(-1) || shm == 0){
		fprintf(stderr,"can't attach %d\n",n);
		exit(2);
	}
	printf("%.128s",shm);
	exit(0);
}