#include <stdio.h> 
#include <errno.h> 
#include <sys/shm.h> 

int detachandremove(int shmid, void *shmaddr) {
   int error = 0; 

   if (shmdt(shmaddr) == -1)
      error = errno;
   if ((shmctl(shmid, IPC_RMID, NULL) == -1) && !error)
      error = errno;
   if (!error)
      return 0;
   errno = error;
   return -1;
}