Inter-process communication
Introduction
Inter-process communication (IPC) is a mechanism that allows processes to communicate with each other and synchronize their actions. The communication between these two processes can be seen as a method of cooperation between them. Processes can be running on the same computer or on different systems spread over a network.
Overview
IPC is a fundamental aspect of concurrent and distributed systems. It is used in operating systems, network services, and distributed systems. IPC mechanisms are widely used in operating systems to control and synchronize processes, share data between them, and facilitate their cooperation in performing a task.
Types of Inter-process Communication
There are several types of IPC, each with its own characteristics and use cases. These include:
- Pipes: This is a method of IPC that allows one process to send data to another process. The data is written to the pipe by one process and read from the pipe by the other. This is a unidirectional form of IPC.
- Message passing: This is a method of IPC where messages are sent from one process to another. The sending process continues execution while the receiving process is normally blocked until the message is received.
- Shared memory: In this method, multiple processes are able to access the same memory space. This is a very efficient form of IPC as it does not involve any data copying.
- Sockets: This is a method of IPC that is used for communication between processes over a network. Sockets provide a standard interface for communication between processes.
Pipes
Pipes are a method of IPC that originated in Unix and have since become a standard part of most operating systems. A pipe is a section of shared memory that processes use for communication. The process that creates a pipe is the parent process. The parent process uses the pipe to communicate with its child processes.
Message Passing
Message passing is a form of IPC that involves sending and receiving messages between processes. Messages are sent to a message queue, which stores the messages until they are received by another process. The sending process continues execution while the receiving process is normally blocked until the message is received.
Shared memory is a powerful form of IPC that allows multiple processes to share a single region of memory. Shared memory is the fastest form of IPC because it can be done at memory speeds when within a computer. It is also the most complex to use as it requires synchronization between processes to prevent them from reading and writing to the same area at the same time.
Sockets
Sockets are a method of IPC that allows processes to communicate over a network. A socket is an endpoint for communication. Each socket is bound to a port number so that the TCP layer can identify the application that data is destined to be sent to. An endpoint is a combination of an IP address and a port number.
Conclusion
Inter-process communication is a critical aspect of modern computing systems. It allows processes to cooperate, share data, and synchronize their actions. Understanding the different types of IPC and how they work is essential for anyone working in the field of computer science or software engineering.