What is the role of drawable parameter in XCreatePixmap()

[Mustafizur Rahaman]

Hi,

We pass a drawable parameter as input while calling XCreatePixmap().Now 
this drawable can be either a X window Id(which we got from a previous 
call to XCreateWindow) Or, this drawable could be a X pixmap id(which we 
got from a previous XCreatePixmap() call).

I checked the xlib manual and it mentions that this drawable parameter 
is used to just determine the screen number, where the new pixmap will 
be created. I want to know is there any other significance of this 
drawable? Is there any difference between the behavior of when we pass X 
window id as drawable to XCreatePixmap and when we pass a X pixmap id as 
drawable to another XCreatePixmap call.