[Development] Building Always on same path?

[Reynaldo San Juan]

Hi
I'm developing a litle app and
I want to build always inside the user Home path. on Unix based systems 
is very easy puting the "~"char at the begining of the path,
but o Windows "~" doesn't work, I used instead "%userprofile%" , like 
enviroment variable, but isn't working neither.
Could you tell me how could I do that and use inside the .pro file to 
refer to enviroment vars?

regards,
Rey San Juan
PD: Be nice with me, I'm a new one here :D & sorry my english.