If you have one of the newer versions of GhostScript which can read
PDF  files, then there's no reason you can't read PDF files in XV,
either.  

All you need is this simple patch to detect PDF files as being
'PostScript-y'.

--jhb, 4/1/98

--- xv-3.10a.orig/xv.c	1995-01-19 10:08:43.000000000 -0800
+++ xv-3.10a/xv.c	2005-05-29 23:56:58.000000000 -0700
@@ -2625,6 +2625,10 @@
 	   strncmp((char *) magicno, "\004%!", (size_t) 3)==0)   rv = RFT_PS;
 #endif
 
+#ifdef GS_PATH
+  else if (strncmp((char *) magicno, "%PDF",   (size_t) 4)==0)   rv = RFT_PS;
+#endif
+
   return rv;
 }