Questions tagged [qmutex]
The QMutex class, part of the Qt framework, provides access serialization between threads.
qmutex
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Non-symmetric mutex
I have an unknown number of processes that create independent data, and one function that modifies all existing data. I need to be able to prevent the modification of data when it is being created (or ...
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How to block a thread until a slot is received
I'm using Qt 6.6.1.
I defined a class MyThread:
class MyThread: public QThread
As an inner class, I defined a class WakeUpEvent in the private section of the .h file:
private:
class WakeUpEvent : ...
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2
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How to use QMutex correctly with QThread?
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
import time
import sys
import numpy as np
class Mainthread(QThread):
def __init__(self, parent):
super().__init__(...
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What is the difference between "thread and QThread" and "mutex and QMutex" in Python?
I'm doing research on multithreads in python. Can you explain the differences between "thread and QThread" and "mutex and QMutex"?
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Multipass totally broken on MacOS & multipassd error logs
The com.canonical.multipassd service is constantly logging errors on my Mac and multipass won't work at all, even after reinstalling, rebooting, and updating my Mac.
In an attempt to use my GPU in a ...
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5
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Do I need a QMutex for variable that is accessed by single statement?
In this document, a QMutex is used to protect "number" from being modified by multiple threads at same time.
I have a code in which a thread is instructed to do different work according to a ...
- 943
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229
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And odd use of conditional variable with local mutex
Poring through legacy code of old and large project, I had found that there was used some odd method of creating thread-safe queue, something like this:
template < typename _Msg>
class WaitQue: ...
- 14.2k
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QThread, two QTimer's and QMutex deadlock
I have QObject with method, protected with QMutex. This method can be directly run from many threads. And I have another QObject living in other QThread with two QTimers. Timers have different ...
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1
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780
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QMutex::lock() taken by same QThread several times consecutively
I have a QThread spawned off from my main that is doing a synchronous read on a device. The read has a 1000ms timeout. The read is wrapped in a forever loop, and the read is protected with a QMutex. ...
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QMutex locked by unknown thread
In the following code, I get an ASSERT in unlock (), because lockingThreads (a QList<QThread*>) does not contain the unlocking (current) thread.
Examining lockingThreads, I find an "ntdll" ...
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How to fix "In Qt two timer to one function, use qmutex will qeventloop for sleep"
I have some code use qtcpsocket to write and read,
write-->sleep-->read;
and ui had 2 and more timer to use this function; by i want i run synchronous;so i add mutex to lock it; by it deadlock;
...
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QMutex: destroying locked mutex
Given the following code:
#include <chrono>
#include <ctime>
#include <functional>
#include <iostream>
#include <thread>
#include <utility>
#include <QFuture&...
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Is threading.Lock() compatible with QThread() and is QMutex() compatible with python threads?
I'm using Python 3.7 (with PyQt5 for the GUI) on a Windows 10 computer. My application needs some multithreading. To do that, I use QThread().
I need to protect some code with a mutex. I figured I've ...
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"Attempting to reference a deleted function" after adding QMutex to class
I am building an application with Qt5. My program builds and runs fine, but there is a collision between two threads accessing a data structure. I have a QList of CanMessage objects, and I want to ...
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Crash creating QMutexLocker from child QThread
I have QMutex and QQueue as member in QThread based class. I'm locking QMutex (by QMutexLocker) in popEvent and pushEvent metods. When I lock it in push method called from main thread it works. When I ...
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