Not even my main fuction runs - c

Question

I cant even get to print "Main" on the screen. It seems like none of my code runs. When i dont specify any command line arguments in prints out the warning. my input file contains integers on each line.
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <unistd.h>
#include <semaphore.h>
#include <sys/types.h>
int patientCount,treatedPatientCount,maxPatient,allRegistered;
int *list;
FILE *input,*output;
sem_t semOutputFile,semGlobalVars;
void* Nurse();
void* Doctor(void *);
int main( int argc, char *argv[] ){
printf("Main");
if(argc != 3){
printf("Command line argument count is different then expected. Aborting!");
return -1;
}
input = fopen(argv[1],"r");
output = fopen(argv[2],"w");
allRegistered = 0;
maxPatient = 5;
treatedPatientCount = 0;
patientCount = 0;
list = malloc(sizeof(int)*maxPatient);
pthread_t nurse,doc1,doc2;
sem_init(&semGlobalVars, 0, 1);
sem_init(&semOutputFile, 0, 1);
pthread_create(&nurse, NULL, &Nurse, NULL);
pthread_create(&doc1, NULL, &Doctor, (void*) 1);
pthread_create(&doc2, NULL, &Doctor, (void*) 2);
pthread_exit(NULL);
}
void* Nurse(){
char buff[255],*eof;
while(1){
eof = fgets(buff, 255, input);
if (eof == NULL) {
allRegistered = 1;
pthread_exit(NULL);
}
int k = atoi(buff);
sem_wait(&semGlobalVars);//Critical region 1 starts
if(patientCount == maxPatient){
maxPatient *=2;
list = realloc(list,sizeof(int)*maxPatient);
}
list[patientCount++] = k;
sem_post(&semGlobalVars);//Critical region 1 ends
sem_wait(&semOutputFile);//Critical region 2 starts
fputs("Nurse registered a patient!\n",output);
sem_post(&semOutputFile);//Critical region 2 ends
sleep(2);
}
}
void* Doctor(void * id){
printf("Doctor");
char buff[255];
int waitTime = 0;
while(1){
printf("%d %d %d",allRegistered,treatedPatientCount,patientCount);
if(allRegistered == 1 && treatedPatientCount==patientCount) pthread_exit(NULL);
sem_wait(&semGlobalVars);//Critical region 1 starts
waitTime = list[treatedPatientCount++];
sem_post(&semGlobalVars);//Critical region 1 ends
sprintf (buff, "Doctor %d treated a patient\n", (int) id);
sem_wait(&semOutputFile);//Critical region 2 starts
fputs(buff,output);
sem_post(&semOutputFile);//Critical region 2 ends
sleep(waitTime);
}
}

Answer 1

You can add exit(0) to the end of main
What exit(0) does is flush all buffers, (and other good things,) making sure anything that was buffered (like that printf of "Main") gets written out.
All C streams (open with functions in <cstdio>) are closed (and flushed, if buffered), and all files created with tmpfile are removed.
http://www.cplusplus.com/reference/cstdlib/exit/