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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#tcp-ip">TCP/IP</a></li>
<li class="level1"><a href="#shared-memory">Shared Memory</a></li>
<li class="level1"><a href="#d-bus-protocol">D-Bus protocol</a></li>
<li class="level1"><a href="#qprocess">QProcess</a></li>
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<h1 class="title">Inter-Process Communication in Qt</h1>
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<p>Qt provides several ways to implement Inter-Process Communication (IPC) in Qt applications.</p>
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<h2>TCP/IP</h2>
<p>The cross-platform QtNetwork 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.</p>
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<h2>Shared Memory</h2>
<p>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.</p>
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<h2>D-Bus protocol</h2>
<p>The QtDBus module is a Unix-only library you can use to implement IPC using the D-Bus protocol. It extends Qt's 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 Qt D-Bus documentation has detailed information on how to use the QtDBus module.</p>
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<h2>QProcess</h2>
<p>The cross-platform class <a href="#qprocess">QProcess</a> 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. <a href="#qprocess">QProcess</a> gives access to the input/output channels of child process by inheriting from QIODevice.</p>
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