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-rw-r--r--src/concurrent/qtconcurrentrun.cpp73
1 files changed, 20 insertions, 53 deletions
diff --git a/src/concurrent/qtconcurrentrun.cpp b/src/concurrent/qtconcurrentrun.cpp
index 18bcf332ac..017f2df480 100644
--- a/src/concurrent/qtconcurrentrun.cpp
+++ b/src/concurrent/qtconcurrentrun.cpp
@@ -1,45 +1,10 @@
-/****************************************************************************
-**
-** Copyright (C) 2016 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the QtConcurrent module of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL$
-** Commercial License Usage
-** Licensees holding valid commercial Qt licenses may use this file in
-** accordance with the commercial license agreement provided with the
-** Software or, alternatively, in accordance with the terms contained in
-** a written agreement between you and The Qt Company. For licensing terms
-** and conditions see https://www.qt.io/terms-conditions. For further
-** information use the contact form at https://www.qt.io/contact-us.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 3 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL3 included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 3 requirements
-** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
-**
-** GNU General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU
-** General Public License version 2.0 or (at your option) the GNU General
-** Public license version 3 or any later version approved by the KDE Free
-** Qt Foundation. The licenses are as published by the Free Software
-** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
-** included in the packaging of this file. Please review the following
-** information to ensure the GNU General Public License requirements will
-** be met: https://www.gnu.org/licenses/gpl-2.0.html and
-** https://www.gnu.org/licenses/gpl-3.0.html.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
/*!
\page qtconcurrentrun.html
\title Concurrent Run
+ \brief A simple way to run a task in a separate thread.
\ingroup thread
The QtConcurrent::run() function runs a function in a separate thread.
@@ -115,6 +80,10 @@
\snippet code/src_concurrent_qtconcurrentrun.cpp 2
+ If you don't need the result (for example, because the function returns
+ \c{void}), using the QThreadPool::start() overload taking a function object
+ is more efficient.
+
As documented above, passing arguments is done like this:
\snippet code/src_concurrent_qtconcurrentrun.cpp 3
@@ -167,18 +136,17 @@
\section2 The mandatory QPromise argument
- The function passed to QtConcurrent::run() in \e {Run With Promise} mode is expected
- to have an additional argument of \c {QPromise<T> &} type, where
- T is the type of the computation result (it should match the type T
- of QFuture<T> returned by the QtConcurrent::runWithPromise()), like e.g.:
+ The function passed to QtConcurrent::run() in \e {Run With Promise} mode
+ is expected to have an additional argument of \c {QPromise<T> &} type, where
+ \c T is the type of the computation result (it should match the type \c T
+ of QFuture<T> returned by QtConcurrent::run()), like e.g.:
\snippet code/src_concurrent_qtconcurrentrun.cpp 9
- The \c promise argument is instantiated inside the
- QtConcurrent::run() function, and its reference
- is passed to the invoked \c aFunction, so the user
- doesn't need to instantiate it by himself, nor pass it explicitly
- when calling QtConcurrent::runWithPromise().
+ The \c promise argument is instantiated inside the QtConcurrent::run()
+ function, and its reference is passed to the invoked \c aFunction, so the
+ user doesn't need to instantiate it, nor pass it explicitly
+ when calling QtConcurrent::run() in this mode.
The additional argument of QPromise type always needs to appear
as a first argument on function's arguments list, like:
@@ -256,7 +224,7 @@
*/
/*!
- \fn QFuture<T> QtConcurrent::run(Function function, ...);
+ \fn template <typename T> QFuture<T> QtConcurrent::run(Function function, ...);
Equivalent to
\code
@@ -287,17 +255,16 @@
running task, fetching multiple results from the called \a function or
monitoring progress reported by the \a function.
- \sa {Concurrent Run (basic mode)}, {Concurrent Run With Promise}
+ \sa {Concurrent Run (basic mode)}, {Concurrent Run With Promise}, QThreadPool::start()
//! [run-description]
*/
/*!
\since 5.4
- \fn QFuture<T> QtConcurrent::run(QThreadPool *pool, Function function, ...);
+ \fn template <typename T> QFuture<T> QtConcurrent::run(QThreadPool *pool, Function function, ...);
- Runs \a function in a separate thread. The thread is taken from the
- QThreadPool \a pool. Note that \a function may not run immediately; \a function
- will only be run once a thread becomes available.
+ Schedules \a function on \a pool. Note that \a function may not run
+ immediately; \a function will only be run once a thread becomes available.
\include qtconcurrentrun.cpp run-description
*/