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.