My Goal is to get outputs from Dining Philosophers C Program. I am using Visual Studio 2013 on Windows 7 to compile and execute C programs. Got errors stating that pthread.h, semaphore.h were not available. Downloaded the same for windows build and included in the project.
Now I get the following 8 errors
warning C4013: 'sleep' undefined; assuming extern returning int
error LNK2019: unresolved external symbol __imp__sem_init referenced in function _main
error LNK2019: unresolved external symbol __imp__sem_wait referenced in function _put_fork
error LNK2019: unresolved external symbol __imp__sem_post referenced in function _put_fork
error LNK2019: unresolved external symbol __imp__pthread_create referenced in function _main
error LNK2019: unresolved external symbol __imp__pthread_join referenced in function _main
error LNK2019: unresolved external symbol _sleep referenced in function _philospher
error LNK1120: 6 unresolved externals
The Code I have used is`
#include<stdio.h>
#include<semaphore.h>
#include<pthread.h>
#define N 5
#define THINKING 0
#define HUNGRY 1
#define EATING 2
#define LEFT (ph_num+4)%N
#define RIGHT (ph_num+1)%N
sem_t mutex;
sem_t S[N];
void * philospher(void *num);
void take_fork(int);
void put_fork(int);
void test(int);
int state[N];
int phil_num[N] = { 0, 1, 2, 3, 4 };
int main()
{
int i;
pthread_t thread_id[N];
sem_init(&mutex, 0, 1);
for (i = 0; i<N; i++)
sem_init(&S[i], 0, 0);
for (i = 0; i<N; i++)
{
pthread_create(&thread_id[i], NULL, philospher, &phil_num[i]);
printf("Philosopher %d is thinking\n", i + 1);
}
for (i = 0; i<N; i++)
pthread_join(thread_id[i], NULL);
}
void *philospher(void *num)
{
while (1)
{
int *i = num;
sleep(1);
take_fork(*i);
sleep(0);
put_fork(*i);
}
}
void take_fork(int ph_num)
{
sem_wait(&mutex);
state[ph_num] = HUNGRY;
printf("Philosopher %d is Hungry\n", ph_num + 1);
test(ph_num);
sem_post(&mutex);
sem_wait(&S[ph_num]);
sleep(1);
}
void test(int ph_num)
{
if (state[ph_num] == HUNGRY && state[LEFT] != EATING && state[RIGHT] != EATING)
{
state[ph_num] = EATING;
sleep(2);
printf("Philosopher %d takes fork %d and %d\n", ph_num + 1, LEFT + 1, ph_num + 1);
printf("Philosopher %d is Eating\n", ph_num + 1);
sem_post(&S[ph_num]);
}
}
void put_fork(int ph_num)
{
sem_wait(&mutex);
state[ph_num] = THINKING;
printf("Philosopher %d putting fork %d and %d down\n", ph_num + 1, LEFT + 1, ph_num + 1);
printf("Philosopher %d is thinking\n", ph_num + 1);
test(LEFT);
test(RIGHT);
sem_post(&mutex);
}`
pthreadsis specific to POSIX. You can't just grab a copy of the header file and expect it to work on Windows. – Keith Thompson