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/*!
\page ipc.html
\title Inter-Process Communication in Qt
\brief Inter-Process communication in Qt applications.
Qt provides several ways to implement Inter-Process Communication
(IPC) in Qt applications.
\section1 TCP/IP
The cross-platform \l{Qt Network} module provides classes that make
network programming portable and easy. It offers high-level
classes (e.g., QNetworkAccessManager, QFtp) that communicate using
specific application-level protocols, and lower-level classes
(e.g., QTcpSocket, QTcpServer, QSslSocket) for implementing
protocols.
\section1 Shared Memory
The cross-platform shared memory class, QSharedMemory, provides
access to the operating system's shared memory implementation.
It allows safe access to shared memory segments by multiple threads
and processes. Additionally, QSystemSemaphore can be used to control
access to resources shared by the system, as well as to communicate
between processes.
\section1 D-Bus protocol
The \l{Qt D-Bus} module is a Unix-only library you can use to
implement IPC using the D-Bus protocol. It extends Qt's
\l{signalsandslots.html} {Signals and Slots} mechanism to the IPC
level, allowing a signal emitted by one process to be connected to
a slot in another process. The \l{Qt D-Bus} documentation has detailed
information on how to use the \l{Qt D-Bus} module.
\section1 QProcess Class
The cross-platform class \l{QProcess} can be used to start external
programs as child processes, and to communicate with them. It provides
an API for monitoring and controlling the state of the child
process. QProcess gives access to the input/output channels of child
process by inheriting from QIODevice.
\section1 Session Management
In Linux/X11 platforms, Qt provides support for session management.
Sessions allow events to be propagated to processes, for example, to
notify when a shutdown occurs. The process and applications can then
perform any necessary operations such as save open documents.
\list
\li \l{Session Management}
\endlist
*/