Argument

 

key

   The key for which the associated semaphore identifier is
   returned.
 

nsems

   Value used to initialize the sem_nsems member of the semid_ds
   data structure. See the description.
 

semflg

   Flag used to initialize the low-order 9 bits of the sem_perm.mode
   member of the semid_ds data structure associated with the new
   semaphore. See the description.
 

value

   The initial value to be given to the semaphore. This argument is
   used only when the semaphore is being created.