15.22 System V IPC

You need to require "sys/ipc.ph" before you can use the symbolic names of the operations.

msgctl id, cmd, args

Calls msgctl(2). If cmd is &IPC_STAT then args must be a variable.

msgget key, flags

Creates a message queue for key. Returns the message queue identifier.

msgsnd id, msg, flags

Sends msg to queue id.

msgrcv id, $var, size, type, flags

Receives a message from queue id into var.

semctl id, semnum, cmd, arg

Calls semctl(2). If cmd is &IPC_STAT of &GETALL then arg must be a variable.

semget key, nsems, size, flags

Creates a set of semaphores for key. Returns the message semaphore identifier.

semop key, ...

Performs semaphore operations.

shmctl id, cmd, arg

Calls shmctl(2). If cmd is &IPC_STAT then arg must be a variable.

shmget key, size, flags

Creates shared memory. Returns the shared memory segment identifier.

shmread id, $var, pos, size

Reads at most size bytes of the contents of shared memory segment id starting at offset pos into var.

shmwrite id, string, pos, size

Writes at most size bytes of string into the contents of shared memory segment id at offset pos.