Use killall

app/src/updaters/appupdater.cpp.autosave

+#include <QDebug>
+#include <QtConcurrent/QtConcurrent>
+
+#include "appimage/update.h"
+#include "appupdater.h"
+
+AppUpdater::AppUpdater(const QString &appImagePath, QObject *parent) : QObject(parent), appImagePath(appImagePath), updateHelper(nullptr)
+{
+    connect(this, &AppUpdater::updateAvailable, &updateDialog, &AppUpdateDialog::showUpdateConfirmationMessage);
+    connect(&updateDialog, &AppUpdateDialog::updateRequested, this, &AppUpdater::doUpdate);
+    connect(&updateDialog, &AppUpdateDialog::restartRequested, this, &AppUpdater::doRestart);
+
+    connect(&updateDialog, &AppUpdateDialog::rejected, this, &AppUpdater::stop);
+}
+
+void AppUpdater::setSilentLookup(bool value)
+{
+    silentLookup = value;
+}
+
+void AppUpdater::doUpdateLookUp()
+{
+    if (appImagePath.isEmpty()) {
+        qWarning() << "Self-updates disabled: No app file provided.";
+        return;
+    }
+
+    if (!silentLookup)
+        updateDialog.show();
+
+    QtConcurrent::run([=]() {
+        appimage::update::Updater updater(appImagePath.toStdString());
+
+        bool updateAvailable; // this is an output parameter!!!
+        updater.checkForChanges(updateAvailable);
+
+        if (updateAvailable) {
+            qDebug() << "Update available";
+            emit this->updateAvailable();
+        }
+
+    });
+}
+
+void AppUpdater::doUpdate()
+{
+    if (appImagePath.isEmpty()) {
+        qWarning() << "Self-updates disabled: No app file provided.";
+        return;
+    }
+
+
+    if (updateHelper !=nullptr)
+        delete updateHelper;
+
+    updateHelper = new appimage::update::Updater(appImagePath.toStdString());
+
+    updateHelper->start();
+
+    progressCheckTimer.setInterval(200);
+    progressCheckTimer.start();
+
+    connect(&progressCheckTimer, &QTimer::timeout, this, &AppUpdater::checkUpdateProgress);
+}
+
+void AppUpdater::doRestart()
+{
+    QProcess::startDetached("killall", {"pling-store"});
+
+    if (updateHelper != nullptr) {
+        std::string pathToNewFile;
+        updateHelper->pathToNewFile(pathToNewFile);
+
+        if (!pathToNewFile.empty()) {
+            QString path = QString::fromStdString(pathToNewFile);
+            QFile::setPermissions(path, QFileDevice::ReadUser | QFileDevice::ExeUser);
+
+
+            QProcess proc;
+            proc.setEnvironment(getCleanSystemEnvironment());
+
+            qDebug() << proc.environment();
+            if (proc.startDetached(path)) {
+                updateDialog.accept();
+            } else
+                updateDialog.showErrorMessage("Unable to start: " + path);
+        }
+    }
+}
+
+void AppUpdater::stop()
+{
+}
+
+void AppUpdater::checkUpdateProgress()
+{
+    using namespace appimage::update;
+    auto state = updateHelper->state();
+    switch (state) {
+    case Updater::INITIALIZED:
+        break;
+    case Updater::RUNNING:
+        double progress;
+        updateHelper->progress(progress);
+        updateDialog.showProgress(progress*100);
+        break;
+    case Updater::STOPPING:
+        break;
+    case Updater::SUCCESS:
+        updateDialog.showCompletionMessage();
+        progressCheckTimer.stop();
+        break;
+    case Updater::ERROR:
+        updateDialog.showErrorMessage(tr("Update failed"));
+        progressCheckTimer.stop();
+        break;
+    }
+}
+
+QStringList AppUpdater::getCleanSystemEnvironment()
+{
+    QString appDirPath = qgetenv("APPDIR");
+
+    QProcessEnvironment systenEnvironemnt = QProcessEnvironment::systemEnvironment();
+    QProcessEnvironment  processEnvironment;
+
+    for (QString key: systenEnvironemnt.keys()) {
+        QString value = systenEnvironemnt.value(key);
+
+        QStringList oldValue = value.split(":");
+        QStringList newVaule;
+        for (const QString &valueSection: oldValue)
+            if (!valueSection.contains(appDirPath))
+                newVaule << valueSection;
+
+        if (!newVaule.empty())
+            processEnvironment.insert(key, newVaule.join(":"));
+    }
+
+    return processEnvironment.toStringList();
+//    return {"DISPLAY=:0"};
+}
+