Communication between processes is valuable in a multitasking operating system to enable concurrent processes to work together. Queues are one of three forms of interprocess communication (IPC), the other forms of IPC being semaphores and pipes.

This chapter describes how to create and use queues. Queues enable one or more processes to transfer data to a specific target process.

Note: The queues used for interprocess communication should not to be confused with the message queues used for communication between Presentation Manager (PM) and PM applications, nor with the printer queues used by the print spooler in managing print jobs.