Reference for unit 'ipc': Types

`key_t`		Alias for TKey type
`msglen_t`		Message length type
`msgqnum_t`		Message queue number type
`PIPC_Perm`		Pointer to TIPC_Perm record.
`PMSG`		Pointer to TMSG record
`PMSGbuf`		Pointer to TMsgBuf rcord
`PMSQid_ds`		Pointer to TMSQid_ds
`PSEM`		Pointer to `TSEM`
`PSEMbuf`		Pointer to TSembuf record.
`PSEMid_ds`		Pointer to TSEMid_ds record.
`PSEMinfo`		Pointer to TSEMinfo record.
`PSEMun`		Pointer to TSEMun record
`PShmid_DS`		Pointer to TSHMid_ds record.
`TIPC_Perm`		Record used in all IPC systems to specify the permissions.
`TKey`		Type returned by the ftok key generating function.
`TMSG`		Record used in the handling of message queues. Do not use directly.
`TMSGbuf`		Generic message data record
`TMSQid_ds`		Record returned by the msgctl call, contains all data about a message queue.
`TSEM`		Semaphore type (opaque)
`TSEMbuf`		Record used in semop call.
`TSEMid_ds`		Structure returned by the semctl call, contains all data of a semahore
`TSEMun`		Record used in semctl call.
`TSHMinfo`		Record used by the shared memory system, Do not use directly.