Implement the Producer – Consumer problem using semaphores (using UNIX system calls).

#include<stdio.h>
#include<stdlib.h>

int full=0,empty=3,x=0;

main()

{

int n;

void producer();
void consumer();
int wait(int);


int signal(int);
printf("\n1.PRODUCER\n2.CONSUMER\n3.EXIT\n");
while(1)

{

printf("\nENTER YOUR CHOICE\n");

scanf("%d",&n);

switch(n)

{

case 1:

if(empty!=0)

producer();

else

printf("BUFFER IS FULL");

break;

case 2: if(full!=0)

consumer();

else

printf("BUFFER IS EMPTY");

break;

case 3:

exit(0);

break;

}

}

}

int wait(int s)

{

return(--s);

}

int signal(int s)

{

return(++s);

}

void producer()

{



full=signal(full);

empty=wait(empty);

x++;

printf("\nproducer produces the item%d",x);


}

void consumer()

{



full=wait(full);

empty=signal(empty);

printf("\n consumer consumes item%d",x); x--;



}