POSIX and System V shared memory functions differ

POSIX standard
Shm_open:Open or create a shared memory area
shm_unlink: Delete a shared memory area
ftruncate: resizing a file or shared memory area
Sem_open:CreateSignal Volume
Sem_wait: Wait for the semaphore
Sem_post: Send Signal volume
Sem_close: Off Signal volume

System v Standard
Ftok:Generate key
shmget: Create shared memory
shmdt: delete shared memory Area
Semget: create semaphore
Semop: Operation Semaphore
Semctl: Control semaphore


briefly explain the IPCS command and the IPCRM command.
Obtain IPC information:
IPCS [-m|-q|-s]
-m outputs information about shared memory
-Q output Information about information queue (Message queue)
-s output about the "breaker" ( Semaphore) Information
%ipcs-m

Delete IPC
ipcrm-m|-q|-s shm_id
%ipcrm-m

SYSTEMV Code Delete:
Semctl (m_ sem_id,0, Ipc_rmid);
Shmctl (m_shm_id,ipc_rmid,null);

Linux feels good for SYSTEMV, many older versions do not support POSIX-related functions

POSIX and System V shared memory functions differ