I'm trying to create a semaphore, but my code doesn't pass the first check and prints: "sem_open/producer: No such file or directory".

Note that SEM_CONSUMER_FNAME and SEM_PRODUCER_FNAME were defined in shared_memory.h.

Can someone lend me a hand, please?

#include <stdio.h>
#include <stdlib.h>
#include <string.h> 
#include <sys/types.h>
#include <signal.h>
#include <unistd.h>
#include "map.h"
#include <errno.h>
#include "shared_memory.h"
#include <semaphore.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <fcntl.h> 
#include <sys/stat.h> 


int main(){     
        
    //Remove semaphores with same name;
    sem_unlink(SEM_CONSUMER_FNAME);
    sem_unlink(SEM_PRODUCER_FNAME);  
    
    //Setup some semaphores
    sem_t *sem_prod = sem_open(SEM_PRODUCER_FNAME, IPC_CREAT, 0660, 0);
    if (sem_prod == SEM_FAILED){
        perror("sem_open/producer");
        exit(EXIT_FAILURE);
    }   
    
    sem_t *sem_cons = sem_open(SEM_CONSUMER_FNAME, IPC_CREAT, 0660, 1);
    if (sem_cons == SEM_FAILED) {
        perror("sem_open/consumer");
        exit(EXIT_FAILURE);
    }

CodePudding user response：

According to this man page,

The oflag argument specifies flags that control the operation of the call. (Definitions of the flags values can be obtained by including <fcntl.h>.) If O_CREAT is specified in oflag, then the semaphore is created if it does not already exist.

That is O_CREAT, not IPC_CREAT.