Raster operations in GSS VDI

[Ted Campbell]

I've been working with the GSS VDI implementation for the Unix PC.
One set of functions obviously missing are those which deal with 
raster operations, i.e., the ANSI standard functions vro_cpyfm()
and vrt_cpyfm().  These functions read a portion of the screen 
into RAM, and are critical for many graphics operations (like 
writing a window over an area of the screen and then redrawing
it).

In the absence of these functions, are theire any other (quick)
ways of performing bitblits on the Unix PC?  I'll appreciate
any suggestions.