How can I intercept GetDC calls?

jrw · Post by **jrw** » Fri Aug 01, 2003 12:48 am

Im writing a shareware image manipulation/morphing program. The full version will allow the user to save their picture but it will contain a shareware banner much like HyperSnapDX. Im worried that many people will simply grab the application window and then just save it in some other freeware screengrab utility.

So how can I intercept any calls to GETDC ? because I want to have the same type of banner accross the picture if someone attempts to grab the current image they are editing into another program.

I hope that made some kind of sense

netmon · Post by **netmon** » Wed Aug 06, 2003 7:42 am

you have more to worry about then people using getdc.. just a simple print screen will do the trick. but back to your original question.. getdc isnt a windows message that can be detected. the only thing i could think of would be to look at what processes are running and maybe kill those off that you dont want to run (exitprocess). This may not be such a good idea though. although you might want to close out your own application and have it refuse to run if you detect another program is running.

I would simply live with this fact and maybe cripple the software in some other way.

jrw · Post by **jrw** » Wed Aug 06, 2003 4:51 pm

I think it would be possible but its going to be difficult to write in purebasic.

The best way to cripple an animation program is for a watermark to be embedded but it gets messy if you force a watermark on a project which is work-in-progress.

I might have to write some c++ code as a background process, that should do the trick.