• Table of Contents

Inter-Process Communication

IPC (Inter-process communication) involves communication between processes running either on the same machine or on different machines. It can be achieved through various methods such as:

• Shared memory: Allows processes to share data by mapping a section of memory that can be accessed by multiple processes.
• Remote Procedure Call (RPC): Utilizes a procedure call abstraction to invoke procedures located in remote processes, enabling communication between distributed systems.
• Message Passing: Involves the explicit exchange of messages between processes, facilitating communication across different machines or within the same machine.

IPC — Shared Memory

Shared memory is a type of IPC mechanism where multiple processes can access the same physical memory address space. It utilizes mechanisms such as pipes, queues, and sockets for communication between processes within the same machine.

Multi-Process Pipe

Pipe() creates a communication channel (pipe) between two processes. Each process has one end of the pipe.

Figure 6.1 Pipe.

When using Pipe(), two Connection objects (conn1 and conn2) are returned.

It allows the transfer of structured data between processes.

• In a duplex pipe, both ends can send and receive data. Both processes are used to send() and recv() data between processes.
• In a simplex pipe, one end sends, and the other end receives data. Only one process can send() and the other recv() data.

Multi-Process Queue

Queue() provides a shared queue abstraction for inter-process communication, enabling multiple processes to exchange structured data.

Figure 6.2 Queue.

The queue facilitates the transfer of structured data between processes and supports three variants: