program in C reader-writer using semaphore - c

Question

I have been trying to execute this program in C.
I used the following commands to compile and run the code:
gcc -o rw rw.c -lpthread
./rw ricr ricb roocr roocb wicr wicb woocr woocb nr nw
I am getting the following warning on the following command gcc -o rw rw.c -lpthread:
I am getting the following output from this command
./rw ricr ricb roocr roocb wicr wicb woocr woocb nr nw:
The above picture shows the output which is incorrect.
Required output:
enter the number of readers : (user entering some number)
enter the number of writers : (user entering some number of writers)
and output.
I have not been getting the desired output and hence need some help.
Thank you in advance.
#include <stdio.h>
#include <pthread.h>
#include <semaphore.h>
#include <stdlib.h>
#include <time.h>
#include <errno.h>
#define RANGE 1000000000
#define BASE 500000000
int rICrange = RANGE;
int rICbase = BASE;
int rOOCrange = RANGE;
int rOOCbase = BASE;
int wICrange = RANGE;
int wICbase = BASE;
int wOOCrange = RANGE;
int wOOCbase = BASE;
int keepgoing = 1;
int totalReads = 0;
int totalWrites = 0;
int read_count = 0;
sem_t mutex, rw_mutex;
void threadSleep(int range, int base) {
struct timespec t;
t.tv_sec = 0;
t.tv_nsec = (rand() % range) + base;
nanosleep(&t, 0);
}
void *readers(void *args) {
int id = *((int *) args);
threadSleep(rOOCrange, rOOCbase);
while (keepgoing) {
sem_wait(&mutex);
totalReads++;
read_count++;
if(read_count == 1)
sem_wait(&rw_mutex);
sem_post(&mutex);
printf("Reader %d starting to read\n", id);
threadSleep(rICrange, rICbase);
printf("Reader %d finishing reading\n", id);
sem_wait(&mutex);
read_count--;
if(read_count == 0)
sem_post(&rw_mutex);
sem_post(&mutex);
threadSleep(rOOCrange, rOOCbase);
}
printf("Reader %d quitting\n", id);
}
void *writers(void *args) {
int id = *((int *) args);
threadSleep(wOOCrange, wOOCbase);
while (keepgoing) {
sem_wait(&rw_mutex);
totalWrites++;
printf("Writer %d starting to write\n", id);
threadSleep(wICrange, wICbase);
printf("Writer %d finishing writing\n", id);
sem_post(&rw_mutex);
threadSleep(wOOCrange, wOOCbase);
}
printf("Writer %d quitting\n", id);
}
int main(int argc, char **argv) {
int numRThreads = 0;
int numWThreads = 0;
if (argc == 11) {
rICrange = atoi(argv[1]);
rICbase = atoi(argv[2]);
rOOCrange = atoi(argv[3]);
rOOCbase = atoi(argv[4]);
wICrange = atoi(argv[5]);
wICbase = atoi(argv[6]);
wOOCrange = atoi(argv[7]);
wOOCbase = atoi(argv[8]);
numRThreads = atoi(argv[9]);
numWThreads = atoi(argv[10]);
}
else {
printf("Usage: %s <reader in critical section sleep range> <reader in critical section sleep base> \n\t <reader out of critical section sleep range> <reader out of critical section sleep base> \n\t <writer in critical section sleep range> <writer in critical section sleep base> \n\t <writer out of critical section sleep range> <writer out of critical section sleep base> \n\t <number of readers> <number of writers>\n", argv[0]);
exit(-1);
}
pthread_t RThreads[numRThreads];
pthread_t WThreads[numWThreads];
int R_id[numRThreads];
int W_id[numWThreads];
sem_init(&mutex, 0, 1);
sem_init(&rw_mutex, 0, 1);
int i;
for(i = 0; i < numRThreads; i++) {
R_id[i] = i + 1;
pthread_create(&RThreads[i], 0, readers, &R_id[i]);
}
for(i = 0; i < numWThreads; i++) {
W_id[i] = i + 1;
pthread_create(&WThreads[i], 0, writers, &W_id[i]);
}
char buf[256];
scanf("%s", &buf);
keepgoing = 0;
for(i = 0; i < numRThreads; i++)
pthread_join(RThreads[i], 0);
for(i = 0; i < numWThreads; i++)
pthread_join(WThreads[i], 0);
printf("Total number of reads: %d\nTotal number of writes: %d\n",
totalReads, totalWrites);
}