If Source is not the current context for the thread issuing the request, the state of the Source is undefined. Not all values for OpenGL state can be copied. For example, pixel pack and unpack state, render mode state, and select and feedback state cannot be copied using this subroutine. The state that is manipulated by the glPushAttrib subroutine is the only one that can be copied. Parameters dpy Specifies the connection to the X server.
Source Specifies the source context.
Destination Specifies the destination context. Mask Specifies which portions of the Source state are to be copied to the Destination . Notes Two rendering contexts share an address space if both are nondirect and use the same server, or if both are direct but owned by a single process. A process is a single execution environment, implemented in a single address space, consisting of one or more threads. A thread is one of a set of subprocesses that share a single address space, but maintain separate program counters, stack spaces, and other related global data.