numlock: initial code

modified from https://msdn.microsoft.com/en-us/library/ms646304(VS.85).aspx
myfreeer · May 13, 2017 · 123d522 · 123d522
1 parent 0a05401
commit 123d522
Showing 1 changed file with 30 additions and 0 deletions.
diff --git a/numlock.c b/numlock.c
@@ -0,0 +1,30 @@
+#include <windows.h>
+
+void SetNumLock(BOOL bState) {
+  BYTE keyState[256];
+
+  GetKeyboardState((LPBYTE) & keyState);
+  if ((bState && !(keyState[VK_NUMLOCK] & 1)) ||
+    (!bState && (keyState[VK_NUMLOCK] & 1))) {
+    // Simulate a key press
+    keybd_event(VK_NUMLOCK,
+      0x45,
+      KEYEVENTF_EXTENDEDKEY | 0,
+      0);
+
+    // Simulate a key release
+    keybd_event(VK_NUMLOCK,
+      0x45,
+      KEYEVENTF_EXTENDEDKEY | KEYEVENTF_KEYUP,
+      0);
+  }
+}
+
+int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd) {
+  if (lstrlen(lpCmdLine) > 0) {
+    SetNumLock(FALSE);
+  } else {
+    SetNumLock(TRUE);
+  }
+  return 0;
+}