COMMENT ⊗   VALID 00004 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00002 00002	%\read16 to\pagenumber
C00003 00003	\hbadness=-1
C00005 00004	% now we print the answers, if any
C00006 ENDMK
C⊗;
%\read16 to\pagenumber
\input manmac
\tenpoint
\pageno=800
%\pageno=\pagenumber
\def\rhead{Experimental Pages for The \TeX book}
\def\chapno{ X}
{\catcode`\%=12 \immediate\write\ans{% Answers for galley proofs:}}
\hbadness=-1
\ddanger Everyone who makes extensive use of a powerful macro facility
encounters situations when the macros do surprising things. We have
already mentioned the possibility of setting |\tracingmacros=1|, in order
to see when \TeX\ expands macros and what arguments it finds. There's also
another helpful way to watch what \TeX\ is doing: If you set
↑|\tracingcommands||=1|, \TeX\ will show every command that it executes,
as we saw in Chapter~13.  Furthermore, if you set
|\tracingcommands=2|, \TeX\ will show all conditional commands and
their outcomes, as well as the unconditional commands that are actually
performed or expanded. This diagnostic information goes into your log
file. You can also see it on your terminal, if you say
↑|\tracingonline||=1|. \ (Incidentally, if you make |\tracingcommands|
greater than~2, you get the same information as when it equals~2.) \
Similarly, ↑|\tracingmacros||=2| will trace |\output|, |\everypar|, etc.

\bye
% now we print the answers, if any

% that blank line will stop an unfinished \answer
\immediate\closeout\ans
\vfill\eject
\ninepoint
\input answers
\bye