An Inter-Process Communication (IPC) is a communication between two or more processes. They can be instances of the same application or different applications. The Qt framework provides multiple modules to help you implement a communication between your applications. Most of these modules are cross-platform. Let's talk about the IPC tools that can be used in a Qt application.
The first tools are the TCP/IP sockets. They provide a bidirectional data exchange over a network. Therefore, you can use them to talk with processes on different computers. Moreover, the loopback interface allows you to communicate with processes running on the same computer. All the required classes are inside the QtNetwork module. This technique relies on a client-server architecture. Here is an example of the server part:
QTcpServer* tcpServer = new QTcpServer...