Multi tool use

PThread Segmentation Fault, Incrementor/Decrementor

I keep getting a Seg Fault, im assuming its trying to access past DECREMENTORS 4 that doesn't exit.

I added in a couple of print statements to help narrow the problem.

What im trying to create is a simple increment, decrement program of a threads and variables.

I've also thought about using a struct to store the variables however im unsure if that would be a good idea or not.

/* readerswriters.c */
#include <signal.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <time.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <pthread.h>
#include <semaphore.h>

#define READERS 10
#define INCREMENTORS 5
#define DECREMENTORS 4

sem_t s;
int sum = 0;
int counter = 0;
int total = 0;

void *incrementorfunc(void *arg)

int *me;

me = (int *)arg;
sem_wait(&s);
sum++;
printf("Incrementor %d set sum = %dn", *me, sum);
sem_post(&s);

pthread_exit(NULL);



void *decrementorfunc(void *arg)


int *me;
me = (int *) arg;

//Problem is in here i believe
sem_wait(&s);
sum--;
printf("Decrementor %d set sum = %dn", *me, sum);
sem_post(&s);

//printf("hellon");
pthread_exit(NULL);



int main(void)

int i;
pthread_t iID[INCREMENTORS];
int increID[INCREMENTORS];

pthread_t dID[DECREMENTORS];
int decreID[DECREMENTORS];

counter = 0;

for(i = 0; i < INCREMENTORS; i++)
increID[i] = i;

for(i = 0; i < DECREMENTORS; i++)
decreID[i] = i;

sem_init(&s, 0, 1);

for(i = 0; i < INCREMENTORS; i++)
pthread_create(&iID[i], NULL, incrementorfunc, (void *)&increID[i]);

for(i = 0; i < DECREMENTORS; i++)
pthread_create(&dID[i], NULL, decrementorfunc, (void *)&decreID[i]);


for(i = 0; i< INCREMENTORS; i++)
pthread_join(increID[i], NULL);


for(i = 0; i < DECREMENTORS; i++)
pthread_join(decreID[i], NULL);


return 0;



pthread_join()

pthread_join(increID[i], NULL)

pthread_join(iID[i], NULL);

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