I did tried to use xv to bring in the xwd file but xv complaint that my xwd
file is not in a recognized format...
I too have found that xv won't read my X dumps, which strikes me as odd. OK, I
know I can use the 'grab' option to bypass the dump altogether, but
occasionally I need to capture a pop-up window which involves an active mouse.
The only way I can see of doing that is to use a <sleep 10; xwd -root> routine.
That dump then requires an xwdtopnm conversion to be readable by xv.