main.c

linux terminal thread semophores

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <stdio.h>
#include <string.h>
#include <sys/shm.h>
#include <sys/wait.h>

struct msgbuf {
                long mtype;       /* message type, must be > 0 */
                char mtext[6];    /* message data */
            };

int main()
{
	pid_t PID1,PID2,*p;
	int msgc;
	int shmid,l;
	key_t key,key2;
	struct msgbuf m;
	struct msgbuf m2;
	struct shmid_ds buf;
	PID1=fork();
	m.mtype=1;
	m2.mtype=2;
	if((key = ftok("./",'a'))==-1){
		perror("key");
		return -1;
	 }

  	if((shmid = shmget(key,30*sizeof(int),IPC_CREAT|0640))==-1){
		perror("shmget");
		return -1;
	}
	if((p=(int *)shmat(shmid,NULL,0))==(void *)-1){
		perror("shmat");
		return -1;
 	}
	if((key2 = ftok("./",'a'))==-1){
		perror("key");
		return -1;
	}
  	if((msgc=msgget(key2,IPC_CREAT|0640))==-1){
		perror("msgget");
		return -1;
	}
	
	switch(PID1){
		case -1:
			perror("Fork!");
			return -1;	
		case 0:
			//fiul citeste din coada tip1
			
			l=strlen(m.mtext);
			if(msgrcv(msgc,&m,l,1,0)==-1){
				perror("msgrcv fiu");
				return -1;
			}
			printf("%s \n",m.mtext);
			//fiul trimite in shm ID-ul
			PID2=getpid();
			*p=PID2;
			//memcpy(p,PID2,sizeof(PID2));
			//fiul trimite in coada tip2
  			strcpy(m2.mtext,"bun");l=strlen(m2.mtext);
  			if(msgsnd(msgc, &m2, l+1, 0)==-1){
				perror("snd");
				return -1;
			}
			break;
		default:
			//tata scrie in coada tip1
			strcpy(m.mtext,"bau");l=strlen(m.mtext);
  			if(msgsnd(msgc, &m, l+1, 0)==-1){
				perror("snd");
				return -1;
			}
			//tata citeste din coada tip2
			l=strlen(m2.mtext);
			if(msgrcv(msgc,&m2,l,2,0)==-1){
				perror("msgrcv tata");
				return -1;
			}
			printf("%s %d \n",m2.mtext,strlen(m2.mtext));
			//tata citeste din shm ID-ul si il killereshte
			kill(*p,9);
			printf("Program killarit!\n");
			break;
	}
return 0;
}