What Is Inter Process Communication (IPC)?

Inter Process Communication (IPC) refers to the mechanisms and techniques that allow processes within a computer system to communicate and share data with each other. These processes may belong to the same application or different applications running on the same operating system or across different systems connected via a network.

Purpose of IPC

1. Data Sharing: Facilitates exchange of information between processes.
2. Resource Sharing: Helps manage shared system resources like memory or files.
3. Synchronization: Coordinates process execution to avoid conflicts and ensure consistency.
4. Event Notification: Allows processes to notify each other about events or status changes.

Common Methods of IPC

Here are the widely used IPC mechanisms:

1. Pipes

• Anonymous Pipes: Allow communication between parent and child processes.
• Named Pipes: Enable communication between unrelated processes, even across a network.

2. Message Queues

• A queue that stores messages sent by one process to be retrieved by another process. Useful for asynchronous communication.

3. Shared Memory

• A region of memory shared by multiple processes for direct communication. It’s the fastest IPC method but requires synchronization (e.g., semaphores) to prevent data inconsistency.

4. Sockets

• Provide communication between processes over a network. Commonly used for client-server communication.

5. Signals

• Asynchronous notifications sent to a process to notify it of an event (e.g., termination or interrupt).

6. Semaphores

• Synchronization tools that manage access to shared resources by multiple processes.

7. File-Based Communication

• Processes use files to read/write data for communication. While simple, it is slower compared to other methods.

Types of IPC

1. Local IPC: Communication between processes on the same machine.
2. Remote IPC: Communication between processes across different systems connected via a network.

Examples of IPC in Operating Systems

• Linux/Unix: Uses pipes, message queues, shared memory, and signals.
• Windows: Supports named pipes, mailslots, shared memory, and sockets.

Advantages of IPC

1. Efficient resource sharing.
2. Simplifies coordination and synchronization of processes.
3. Enables distributed computing by supporting network communication.

Disadvantages of IPC

1. Complexity in implementation.
2. Potential security vulnerabilities if not properly managed.
3. Overhead for managing synchronization and data consistency.

Real-Life Applications

• Web servers using sockets to handle client requests.
• Database systems using shared memory for fast access to cached data.
• Process scheduling in operating systems using signals and semaphores.

Inter Process Communication is an essential concept in operating systems and software design, facilitating smooth and efficient interaction between processes.