Several figures (3.1, p. 9, 5.1, p. 20, 5.2, p. 28, A.1, p. 49, and
Table A.1, p. 48) are in idraw format, and may be printed out only
interactively within idraw (part of the X window distribution).  Two
figures (4.1, p. 15 and 5.2, p. 28) are in the xwd format, and may be
printed out only by xpr (also part of the X window distribution). The
Makefile currently calls neither idraw nor xpr.
