Index: LeahiRt/main.cpp
===================================================================
diff -u -r864d025811eb43fd2592bde174e5cb41fa10d783 -rf9c6b488aa4135e8cd47ccd3fdc6c3ae1cd831aa
--- LeahiRt/main.cpp	(.../main.cpp)	(revision 864d025811eb43fd2592bde174e5cb41fa10d783)
+++ LeahiRt/main.cpp	(.../main.cpp)	(revision f9c6b488aa4135e8cd47ccd3fdc6c3ae1cd831aa)
@@ -1,49 +1,57 @@
+#include <signal.h>
+#include <sys/signalfd.h>
+
 #include <QCommandLineOption>
 #include <QCommandLineParser>
 #include <QCoreApplication>
 #include <QDebug>
 #include <QDir>
-#include <signal.h>
+#include <QSocketNotifier>
 
 #include "LeahiRtController.h"
 
 #define log qDebug().noquote()
 
-/*!
- * \brief       signalHandler
- * \details     When application terminates it quits gracefully.
- * \param[in]   sig - The Linux signal causes the termination.
- */
-void signalHandler(int sig)
-{
-    if (sig == SIGINT) {
-        log << "Application terminated by SIGINT";
-        qApp->quit();
-    }
-    else if (sig == SIGTERM) {
-        log << "Application terminated by SIGTERM";
-        qApp->quit();
-    }
-}
-
 int main(int argc, char *argv[])
 {
-    signal(SIGINT , signalHandler);
-    signal(SIGTERM, signalHandler);
+    // Block SIGINT and SIGTERM from normal delivery; redirect them to a fd.
+    sigset_t mask;
+    sigemptyset(&mask);
+    sigaddset(&mask, SIGINT);
+    sigaddset(&mask, SIGTERM);
+    sigprocmask(SIG_BLOCK, &mask, nullptr);
 
+    const int sfd = signalfd(-1, &mask, SFD_CLOEXEC);
+    if (sfd == -1) {
+        qCritical("Failed to create signalfd");
+        return 1;
+    }
+
     QCoreApplication app(argc, argv);
     app.setApplicationName("LeahiRt");
     app.setApplicationVersion("1.0");
-    
+
+    // Notifier runs on the main thread inside the event loop — safe to call quit().
+    QSocketNotifier notifier(sfd, QSocketNotifier::Read);
+    QObject::connect(&notifier, &QSocketNotifier::activated, [&](int fd) {
+        struct signalfd_siginfo info{};
+        (void)read(fd, &info, sizeof(info));
+        if (info.ssi_signo == SIGINT) {
+            log << "Application terminated by SIGINT";
+        }
+        else if (info.ssi_signo == SIGTERM) {
+            log << "Application terminated by SIGTERM";
+        }
+        app.quit();
+    });
+
     QCommandLineParser parser;
     parser.setApplicationDescription("Leahi Real-time Cloud Data Transmission daemon.");
     parser.addHelpOption();
     parser.addVersionOption();
 
     QCommandLineOption configOption(
-        {"c", "config"},
-        "Path to the configuration INI file.",
-        "config",
+        {"c", "config"}, "Path to the configuration INI file.", "config",
         QDir(app.applicationDirPath()).filePath("config/LeahiRt.ini")
     );
     parser.addOption(configOption);