macOS Problem with launchctl Command

[tiku.thakkar]

Hello All,

I have created a sample service on mac called TestService.

I have used the following commands for Starting and Stoping the service from the terminal.

To Load the service:
sudo launchctl load -w /System/Library/LaunchDaemons/TestService.plist

To Start the service:
sudo launchctl start TestService

To Stop the service:
sudo launchctl stop TestService

To Unload the service:
sudo launchctl unload -w /System/Library/LaunchDaemons/TestService.plist

To List the loaded services:
sudo launchctl list

Once I have started the service I am able to see its instance in the Activity Monitor, but even after stopping the service the instance still remains in the Activity Monitor.

I want this instance to be removed from the Activity Monitor as well as from the memory on stoping the service.

Please suggest a solution.

Thanks in advance.
--Twinkle

 

[iSee]

Are you handling the SIGTERM signal? IIRC, you'll want your SIGTERM handler to cause your run loop to exit.

 

[jeremy.king]

You will need to post some source to get help.

 

[tiku.thakkar]

Are you handling the SIGTERM signal? IIRC, you'll want your SIGTERM handler to cause your run loop to exit.

I am a new bee to this MAC related stuff...

Can you please let me know how to find about what kind of signal am I using ?

Actually I have made a simple service/process and started working with that.

Thanks.
Twinkle

 

[tiku.thakkar]

You will need to post some source to get help.

What kind of souce am I supposed to post here?? As I have made very simple process...

 

[iSee]

Post your source code. I'm not sure how else to say it.

Anyway, here's the main file for my own service, which seems to terminate fine. Notice how I register a handler for SIGTERM before the runloop starts:

signal(SIGTERM, &sigtermHandler);

And notice how the handler exits the run loop:

// This is a callback to handle SIGTERM and SIGINT signals
void sigtermHandler(int sig)
{
	CFRunLoopRef rl = CFRunLoopGetCurrent();
	if (rl == NULL)
		exit(1); // something when wrong. Better just exit
	else
		CFRunLoopStop(rl);
}

Here's the whole thing (This service remaps the enter key to the right mouse button--that is what the eventtap stuff is about):

///////////////////////////////////////////////////////
// This program is a daemon that causes the "enter" key
// (not the return key) on your Mac keyboard to act like
// a right-mouse button.
// 
// It requires Mac OS 10.4 (or later, probably) because is uses an event tap
// callback to capture and convert the enter key event at a low level,
// and is designed to run as a lauchd daemon. Event taps and launchd are
// both new to Mac OS 10.4.
//
// The daemon's ability to capture and convert the enter key is not foolproof.
// The enter key will not act as a right mouse button for anything that 
// bypasses the event tap system. I've noticed that Parallels, for example,
// does this. Also, if other event taps are installed, they could have a higher 
// priority. It looks like event taps installed after this one could request
// higher priority.
//
// NOTE: This program must be run as the root user OR access for assistive 
// devices must be enabled to this program to work. When launched with launchd 
// it runs as a root process. However, if you want to run it manually I suggest
// you turn on access for assistive devices (in the universal access pane of
// system preferences.)
//
// NOTE: the log stuff is essentially #ifdef'ed out when compiled in release mode.
// Under debug mode these just resolve to printf statements.

#include <CoreServices/CoreServices.h>
#include <ApplicationServices/ApplicationServices.h>
#include <signal.h>
#include <launch.h>

#include "log.h"

#define SAFE_RELEASE(ref) if ((ref) != NULL) { CFRelease(ref); (ref) = NULL; }

static 	CFStringRef myRunLoopMode = CFSTR("myRunLoopMode");

CGEventRef myEventTapCallback(
   CGEventTapProxy proxy, 
   CGEventType type, 
   CGEventRef event, 
   void *refcon)
{
	if (type == kCGEventKeyDown || type == kCGEventKeyUp)
	{
		CGKeyCode keycode = (CGKeyCode)CGEventGetIntegerValueField(event, kCGKeyboardEventKeycode);

		#ifdef _DEBUG
		{
			CFStringRef msg = CFStringCreateWithFormat(kCFAllocatorDefault, NULL, CFSTR("code: %d, type: %c, auto: %d"), (int)keycode, (type == kCGEventKeyDown) ? 'D' : 'U', (int)(CGEventGetIntegerValueField(event, kCGKeyboardEventAutorepeat) != 0));
			LOGLINE_CF(msg);
			SAFE_RELEASE(msg);
		}
		#endif
		
		if (keycode == 76 /* the "enter" key--note: not the return key */)
		{
			bool isAutoRepeat = (CGEventGetIntegerValueField(event, kCGKeyboardEventAutorepeat) != 0);
			if (isAutoRepeat)
				return NULL;
			
			// change it to a right mouse button event
			CGEventSetType(event, (type == kCGEventKeyDown) ? kCGEventRightMouseDown : kCGEventRightMouseUp);
		}
	}
	
	return event;
}

// This is a callback to handle SIGTERM and SIGINT signals
void sigtermHandler(int sig)
{
	CFRunLoopRef rl = CFRunLoopGetCurrent();
	if (rl == NULL)
		exit(1); // something when wrong. Better just exit
	else
		CFRunLoopStop(rl);
}

int main (int argc, const char * argv[]) 
{
	// Check-in with launchd, as recommended.
	// I couldn't find any documentation on this other than the SampleD code.
	// I am following the SampleD model. As far as I can tell, this is what is 
	// meant by checking in. NOTE: In the sample code I've seen, the call to
	// launch_data_new_string() is not paired with some kind of 
	// a free/dealloc/delete call. 
	{
		launch_data_t checkin_request = launch_data_new_string(LAUNCH_KEY_CHECKIN);
		if (checkin_request == NULL)
			exit(1); // need to add some logging or something here
		else
		{
			launch_data_t checkin_response = launch_msg(checkin_request);
			if (checkin_response == NULL)
				exit(1); // need to add some logging or something here
		}
	}
	
	///////////////////////////////////////////////////

	// Setup the event tap to convert enter key presses to right mouse button presses

	CFRunLoopRef rl = NULL;			// My run loop
	CFMachPortRef mp = NULL;		// The event tap
	CFRunLoopSourceRef rls = NULL;	// The event source for event tap
	
	// get the runloop
	rl = CFRunLoopGetCurrent();
	if (rl != NULL)
		CFRetain(rl);
	
	// create the event tap to watch key up/down events. myEventTapCallback is
	// called when these events occur
	if (rl != NULL)
	{
		mp = CGEventTapCreate(
			kCGHIDEventTap,
			kCGHeadInsertEventTap,
			0x00000000 /* kCGEventTapOptionDefault */,
			CGEventMaskBit(kCGEventKeyDown) | CGEventMaskBit(kCGEventKeyUp),
			myEventTapCallback,
			NULL);
	}
	
	// create the source for the event tap
	if (mp != NULL)
	{
		rls = CFMachPortCreateRunLoopSource(kCFAllocatorDefault, mp, 0);
	}
	
	// add the source to the run loop
	if (rls != NULL)
	{
		CFRunLoopAddSource(rl, rls, myRunLoopMode);
	}
	
	/////////////////////////////////////////////////////

	// Now start the runloop
	
	if (rls != NULL)
	{
		LOGLINE_C("starting...");
		
		// as recommended for launchd daemons, we handle SEGTERM signals.
		// sigtermHandler just tells the runloop to stop. Everything seemed to
		// work fine even when I didn't handle SIGTERM, but this makes me
		// feel better because my cleanup code gets called.
		signal(SIGTERM, &sigtermHandler);
		
		SInt32 result = CFRunLoopRunInMode(myRunLoopMode, 3153600000.0, false); // run for ~100 years (60*60*24*365*100 seconds)
		
		#ifdef _DEBUG
			char buf[1024];
			sprintf(buf, "done! result: %i", result);
			LOGLINE_C(buf);
		#else
			result; // makes warnign go away
		#endif
	}
	
	/////////////////////////////////////////////////////
	
	// cleanup
	if (rls != NULL)
		CFRunLoopRemoveSource(rl, rls, kCFRunLoopCommonModes); // remove the source from the runloop
	SAFE_RELEASE(rls);
	SAFE_RELEASE(mp);
	SAFE_RELEASE(rl);
	
	return 0;
}

You can download the whole project here, if you want: http://www.jjmn.net/dl/EnterKeyRemapperD.zip