Hello everybody,
This is parking program .I defined 4 task (keyboard,enter vehicle,exit vehicle,display)
The program is compile but when I run it and press keys (E,S,F), it does not work.
This program is written for linux.
Can you help me?

#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <stdlib.h>
#include <pthread.h>
#include <semaphore.h>

#define TRUE 1
#define FALSE 0

int places=10;
sem_t evt_in,evt_out,evt_maj;
int fin=FALSE;
pthread_mutex_t mutex_pl;
pthread_cond_t cond_places ;

void * t_keyboard(void *arg){

  char res;
  res=getchar();

  while (fin!=TRUE){
    if(res=='f'){
    fin=TRUE;}
    else { if( res=='e'){
          sem_post(&evt_in);}
      else { if (res=='s'){
            sem_post(&evt_out);
          }
          }
        }


  }
}




void * t_enter (void *arg){
     while (fin!=TRUE){
       sem_wait(&evt_in);
       pthread_mutex_lock(&mutex_pl);
       if (places==0){
         pthread_cond_wait(&cond_places, &mutex_pl);
     }
       printf(" barrier opening(IN)");
     places = places -1;
       sem_post(&evt_maj);
       pthread_mutex_unlock(&mutex_pl);
     }
   }




void * t_exit (void *arg){

while (fin!=TRUE){
       sem_wait(&evt_out);
       pthread_mutex_lock(&mutex_pl);
       if (places==0){
         pthread_cond_wait(&cond_places, &mutex_pl);
     }
       printf("barrier opening IN");
     places = places -1;
       sem_post(&evt_maj);
       pthread_mutex_unlock(&mutex_pl);
     }
   }




void * t_display (void *arg){

while (fin!= TRUE) {
      sem_wait(&evt_maj);
      pthread_mutex_lock(&mutex_pl);
      printf ("places = %d",places);
      pthread_mutex_unlock(&mutex_pl);
      }
}

int main() {

/* declarations  */

  pthread_t thread_keyboard,thread_enter,thread_exit,thread_display;

  int  ikeyboard,ienter, iexit, idisplay;

pthread_mutex_init(&mutex_pl,NULL);
pthread_cond_init(&cond_places,0);
sem_init(&evt_in,0,0);
sem_init(&evt_out,0,0);
sem_init(&evt_maj,0,0);


 iclavier=pthread_create( &thread_keyboard, NULL,&t_keyboard,NULL);
 ientree=pthread_create( &thread_enter, NULL,&t_enter,NULL);
 isortie=pthread_create( &thread_exit, NULL,&t_exit,NULL);
 iaffichage=pthread_create( &thread_display, NULL,&t_display,NULL);



 pthread_join( thread_keyboard, NULL);
 pthread_join( thread_enter, NULL);
 pthread_join( thread_display, NULL);
 pthread_join( thread_exit, NULL);


exit(0);


}

You're checking for lowercase letters, but your question involved uppercase. Really simple suggestion, but that's what sticks out in my mind from scanning your code quickly.