msgrcvid.c

让你了解Unix进程间的通信是如何实现的

#include	"unpipc.h"

#define	MAXMSG	(8192 + sizeof(long))

int
main(int argc, char **argv)
{
	int		mqid;
	ssize_t	n;
	struct msgbuf	*buff;

	if (argc != 2)
		err_quit("usage: msgrcvid <mqid>");
	mqid = atoi(argv[1]);

	buff = Malloc(MAXMSG);

	n = Msgrcv(mqid, buff, MAXMSG, 0, 0);
	printf("read %d bytes, type = %ld\n", n, buff->mtype);

	exit(0);
}