In operating systems, inter-process communication (IPC) refers to the techniques and mechanisms that allow processes to communicate and share data with each other. In C, there are several ways to perform IPC. Here are some of the most common techniques:
Pipes: Pipes are a simple form of IPC that allows communication between two related processes. A pipe is a unidirectional communication channel that can be used to transfer data from one process to another. In C, pipes can be created using the pipe() system call. The data is written to the pipe by one process and read by the other process.
Message Queues: Message Queues provide a more sophisticated form of IPC that allows multiple processes to communicate with each other. A message queue is a buffer that stores messages sent by one process and read by another. In C, message queues can be created using the msgget(), msgsnd(), and msgrcv() system calls.
Shared Memory: Shared memory is a technique that allows multiple processes to access the same area of memory. In C, shared memory can be created using the shmget(), shmat(), and shmdt() system calls. Once the memory is attached, all the processes can read and write to it as if it were their own memory.
Semaphores: Semaphores are a synchronization mechanism that allows processes to coordinate their access to shared resources. A semaphore is a variable that is used to signal the availability of a shared resource. In C, semaphores can be created using the semget(), semctl(), and semop() system calls.
Sockets: Sockets are a form of IPC that allows communication between processes over a network. In C, sockets can be created using the socket(), bind(), listen(), accept(), connect(), send(), and recv() system calls.
Overall, each technique has its own advantages and disadvantages and is suitable for different types of applications. It is important to choose the appropriate technique based on the requirements of the application.