1 files changed, 32 insertions, 0 deletions
diff --git a/src/main.cpp b/src/main.cpp
index 7ba8758..a5fa5db 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -13,9 +13,13 @@
 #include <QIcon>
 #include <QPainter>
 #include <QMap>
+#include <QSocketNotifier>
 
 #include <fcntl.h>              /* Obtain O_* constant definitions */
 #include <unistd.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/socket.h>
 
 #include <iostream>
 
@@ -24,8 +28,12 @@
 #include "x11util.h"
 #include "global.h"
 
+static int sockets[2];
+
 static void createSimpleBackground();
 
+static void sigUsr1(int);
+
 static void messageHandler(QtMsgType type, const QMessageLogContext&, const QString& msg)
 {
     std::cerr << type << ": " << msg.toUtf8().constData() << '\n';
@@ -112,6 +120,21 @@ int main(int argc, char *argv[])
 		primary = screens.begin().key();
 	}
 
+	struct sigaction usr1;
+
+	usr1.sa_handler = &sigUsr1;
+	sigemptyset(&usr1.sa_mask);
+	usr1.sa_flags = SA_RESTART;
+
+	QSocketNotifier *sn = NULL;
+	if (sigaction(SIGUSR1, &usr1, 0) == 0 && ::socketpair(AF_UNIX, SOCK_STREAM, 0, sockets) == 0) {
+		sn = new QSocketNotifier(sockets[1], QSocketNotifier::Read);
+		QObject::connect(sn, &QSocketNotifier::activated, [](int fd) {
+			char tmp[1000];
+			read(fd, tmp, sizeof tmp);
+		});
+	}
+
     // Now set up all the screens
 	QPainter painter(&entire);
     MainWindow *focusWindow = 0;
@@ -120,6 +143,9 @@ int main(int argc, char *argv[])
     	it.next();
         MainWindow *w = new MainWindow(primary == it.key(), it.key(), it.value());
         w->show();
+		if (sn != NULL) {
+			QObject::connect(sn, SIGNAL(activated(int)), w, SLOT(showStandby()));
+		}
         if (w->showLoginForm()) {
             focusWindow = w;
         }
@@ -152,3 +178,9 @@ static void createSimpleBackground()
     img = img.scaled(QApplication::desktop()->size(), Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
     AddPixmapToBackground(img.constBits(), img.width(), img.height(), 24, img.bytesPerLine(), img.byteCount());
 }
+
+static void sigUsr1(int)
+{
+	char a = 1;
+	::write(sockets[0], &a, sizeof(a));
+}