/*
 * msgcrear.c
 * 
 * Copyright 2026 osboxes <osboxes@osboxes>
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301, USA.
 * 
 * Leemos de la cola de mensajes
 * Lectura NO bloqueante
 */


#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>

struct mensaje {
	long mtype;       /* message type, must be > 0 */
	char letra;    /* message data */
};

int main(int argc, char **argv) {
	int msgid = msgget(0xA,0);
	struct mensaje m;
	m.mtype=1L; // tmb podria ser 0L y leeria secuencialmente de todos los tipos de cola
	m.letra=0;
	int rc=0;
	do {
		rc = msgrcv(msgid,&m,1,1L,IPC_NOWAIT);
		if ( rc == 1 ) printf("Lei caracter %c\n",m.letra);
		else           printf("Error en lectura! rc=%d\n",rc);
	} while(rc == 1);
	return 0;
}