Deep understanding of inter-process communication between Linux (IPC)

https://www.ibm.com/developerworks/cn/linux/l-ipc/

Introduction to several main means of interprocess communication under Linux:

1. Pipe and well-known pipe (named pipe): Pipelines can be used for communication between affinity processes, and well-known pipelines overcome the limitations of pipe without name, so that, in addition to having the functions of a pipeline, it allows communication between unrelated processes;
2. Signal (Signal): signal is a more complex mode of communication, used to inform the receiving process of an event occurred, in addition to inter-process communication, the process can also send signals to the process itself; Linux in addition to supporting early UNIX signal semantic function Sigal, Also support the semantics of the POSIX.1 standard signal function sigaction (in fact, the function is based on BSD, BSD in order to achieve a reliable signal mechanism, but also able to unify the external interface, with sigaction function to re-implement the signal function);
3. Message queue (Message Queuing): Messages queue is a linked table of messages, including POSIX Message Queuing system V Message Queuing. A process with sufficient permissions can add messages to the queue, and a process that is given Read permission can read the messages in the queue. Message queue overcomes the disadvantage that the signal carrying information is low, the pipeline can only carry the unformatted byte stream and the buffer size is limited.
4. Shared memory: Allows multiple processes to access the same piece of memory space and is the fastest available IPC form. is designed for inefficient operation of other communication mechanisms. It is often used in conjunction with other communication mechanisms, such as semaphores, to achieve synchronization and mutual exclusion between processes.
5. Semaphore (semaphore): primarily as a means of synchronization between processes and between different threads of the same process.
6. Socket: A more general inter-process communication mechanism that can be used for inter-process communication between different machines. Originally developed by the BSD branch of the UNIX system, it can now be ported to other Unix-like systems: both Linux and System V variants support sockets.

Deep understanding of inter-process communication between Linux (IPC)