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Reference for unit 'ipc': Constants

Constant Description
IPC_CREAT Create if key is nonexistent
IPC_EXCL fail if key exists
IPC_INFO For ipcs call
IPC_NOWAIT return error on wait
IPC_PRIVATE
IPC_RMID Remove resource
IPC_SET set ipc_perm options
IPC_STAT get ipc_perm options
MSGMAX Internal Message control code. Do not use
MSGMNB Internal Message control code. Do not use
MSGMNI Internal Message control code. Do not use
MSG_EXCEPT Internal Message control code. Do not use
MSG_NOERROR Internal Message control code. Do not use
SEM_GETALL Semaphore operation: Get all semaphore values
SEM_GETNCNT Semaphore operation: Get number of processes waiting for resource.
SEM_GETPID Semaphore operation: Get process ID of last operation.
SEM_GETVAL Semaphore operation: Get current value of semaphore
SEM_GETZCNT Semaphore operation: Get number of processes waiting for semaphores to reach zero
SEM_SEMMNI Semaphore operation: ?
SEM_SEMMNS Semaphore operation: ?
SEM_SEMMSL Semaphore operation: ?
SEM_SEMOPM Semaphore operation: ?
SEM_SEMVMX Semaphore operation: ?
SEM_SETALL Semaphore operation: Set all semaphore values
SEM_SETVAL Semaphore operation: Set semaphore value
SEM_UNDO Constant for use in semop
SHM_LOCK This constant is used in the shmctl call.
SHM_R This constant is used in the shmctl call.
SHM_RDONLY This constant is used in the shmctl call.
SHM_REMAP This constant is used in the shmctl call.
SHM_RND This constant is used in the shmctl call.
SHM_UNLOCK This constant is used in the shmctl call.
SHM_W This constant is used in the shmctl call.