On MacOSX 10.14 (Mojave) the behavior changed, the following code runs on 10.13 but fail on 10.14.
The creation of "CGEventTapCreate" is failing (returning null) on Mojave but works before.
Any thoughts? Thanks in advance!
// alterkeys.c
// http://osxbook.com
//
// Complile using the following command line:
// clang -Wall -o alterkeys alterkeys.c -framework ApplicationServices
//
#include <ApplicationServices/ApplicationServices.h>
// This callback will be invoked every time there is a keystroke.
//
CGEventRef
myCGEventCallback(CGEventTapProxy proxy, CGEventType type,
CGEventRef event, void *refcon)
{
// Paranoid sanity check.
if ((type != kCGEventKeyDown) && (type != kCGEventKeyUp))
return event;
// The incoming keycode.
CGKeyCode keycode = (CGKeyCode)CGEventGetIntegerValueField(
event, kCGKeyboardEventKeycode);
// Swap 'a' (keycode=0) and 'z' (keycode=6).
if (keycode == (CGKeyCode)0)
keycode = (CGKeyCode)6;
else if (keycode == (CGKeyCode)6)
keycode = (CGKeyCode)0;
// Set the modified keycode field in the event.
CGEventSetIntegerValueField(
event, kCGKeyboardEventKeycode, (int64_t)keycode);
// We must return the event for it to be useful.
return event;
}
int
main(void)
{
CGEventMask eventMask = CGEventMaskBit(kCGEventLeftMouseDown) |
CGEventMaskBit(kCGEventLeftMouseUp);
CFMachPortRef eventTap = CGEventTapCreate(kCGSessionEventTap, kCGHeadInsertEventTap, 0,
eventMask, myCGEventCallback, NULL);
if (!eventTap) {
fprintf(stderr, "failed to create event tap\n");
exit(1);
}
// Create a run loop source.
CFRunLoopSourceRef runLoopSource = CFMachPortCreateRunLoopSource(
kCFAllocatorDefault, eventTap, 0);
// Add to the current run loop.
CFRunLoopAddSource(CFRunLoopGetCurrent(), runLoopSource,
kCFRunLoopCommonModes);
// Enable the event tap.
CGEventTapEnable(eventTap, true);
// Set it all running.
CFRunLoopRun();
// In a real program, one would have arranged for cleaning up.
exit(0);
}
