1CTWILL(1) General Commands Manual CTWILL(1)
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6 ctwill, ctwill-refsort, ctwill-twinx - translate CWEB to TeX with mini-
7 indexes
8
10 ctwill [options] webfile[.w] [{changefile[.ch]|-} [outfile[.tex]]]
11 ctwill-refsort < indexfile.ref > indexfile.sref
12 ctwill-twinx outfile.tex [outfile.tex ...] > index.tex
13
15 The ctwill program converts a CWEB source document into a TeX file that
16 may be formatted and printed in the usual way. It takes appropriate
17 care of typographic details like page layout and the use of indenta‐
18 tion, italics, boldface, etc., and it supplies extensive cross-index
19 information that it gathers automatically.
20 CWEB allows you to prepare a single document containing all the infor‐
22 mation that is needed both to produce a compilable C/C++ program and to
23 produce a well-formatted document describing the program in as much de‐
24 tail as the writer may desire. The user of CWEB ought to be familiar
25 with TeX as well as C/C++.
26
28 The command line should have one, two, or three names on it. The first
29 is taken as the CWEB input file (and .w is added if there is no exten‐
30 sion). If there is a second name, it is a change file (and .ch is
31 added if there is no extension). The change file overrides parts of
32 the CWEB file, as described in the documentation. If there is a third
33 name, it overrides the default name of the output file, which is ordi‐
34 narily the same as the name of the input file (but on the current di‐
35 rectory) with the extension .tex. If you just want to change the out‐
36 put file name, but don’t have a change file to apply, you can use `-'
37 as the second argument.
38 ctwill is exactly like cweave except that it produces much better docu‐
40 mentation, for which you must work harder. You should run ctwill
41 twice, once to prime the pump and once to get decent answers. More‐
42 over, you must run the output twice through TeX.
43 After tex foo you will have output that looks like final pages except
45 that the entries of mini-indexes won’t be alphabetized. The first run
46 produces a weird file called foo.ref. Say ctwill-refsort < foo.ref >
47 foo.sref and then another tex foo will produce alphabetized output.
48 The ctwill-twinx program compiles a master index for a set of related
50 programs that have been processed by ctwill. The individual programs
51 should define their names with a line of the form \def\title{NAME}.
52 The mini-indexes list identifiers that are used but not defined on each
54 two-page spread. At the end of each section, ctwill gives TeX a list
55 of identifiers used in that section and information about where they
56 are defined.
57 The current meaning of every identifier is initially \uninitialized.
59 Then ctwill reads the .aux file for your job, if any.
60 Before reading the .aux file, ctwill actually looks for a file called
62 system.bux, which will be read if present. And after foo.aux, a third
63 possibility is foo.bux. The general convention is to put definitions
64 of system procedures such as printf into system.bux, and to put defini‐
65 tions found in specifically foo-ish header files into foo.bux. Like
66 the .aux files, .bux files should contain only @$ specifications.
67 The meaning specified by @$...@> generally has four components: an
69 identifier (followed by space), a program name (enclosed in braces), a
70 section number (followed by space), and a TeX part.
71 A special proofmode is provided so that you can check ctwill’s conclu‐
73 sions about cross-references. Run ctwill with the flag +P, and TeX
74 will produce a specially formatted document (without mini-indexes) in
75 which you can check that your specifications are correct.
76 More details how to use ctwill can be found in the first sections of
78 its source code, respectively the change file cweav-twill.ch applicable
79 to the cweave.w source. A complete example with all bells and whistles
80 is described in Mini-Indexes for Literate Programs, pages 225–245 of
81 Knuth’s Digital Typography.
82
84 The present incarnation of ctwill and its utilities tries hard to be a
85 drop-in replacement for the original package. There are, however, a
86 few differences worth noting:
87 • This version is based on the most recent version of CWEB (4.2).
89 • In TeX Live the utility programs are prefixed with ctwill- and the
91 macro files with ct for technical reasons.
92 • Options --help, --quiet, --verbose, --version, and flags -i, -o, -t,
94 and +lX are new in CWEBbin and TeX Live.
95 • Option +lX is accompanied by example wrapper files for ctwimac.tex
97 and ctproofmac.tex with translated captions for German (+ld).
98 • Option +lX is also accompanied by an extended pdfctwimac.tex for pro‐
100 duction of PDF output with active hyperlinks (+lpdf).
101 • ctwill in TeX Live operates silently by default; use the --verbose
103 option to get the original behavior.
104 • File lookup with the environment variable CWEBINPUTS is extended to
106 permit several, colon-separated, paths; see ENVIRONMENT below.
107 • If properly configured, the main program ctwill is localized with the
109 “GNU gettext utilities”.
110
112 Options on the command line may be either turned off with `-' (if they
113 are on by default) or turned on with `+' (if they are off by default).
114 In fact, the options are processed from left to right, so a sequence
115 like --verbose -h will only show the banner line (+b) and the progress
116 report (+p), but leave out the happy message (-h).
117 • +b: print banner line on terminal
119 • +h: print success message on completion
121 • +p: print progress report messages
123 • +q/-q: shortcut for -bhp; also --quiet (default)
125 • +v/-v: shortcut for +bhp; also --verbose
127 • -e: do not enclose C/C++ material in \PB{...}
129 • -f: do not force a newline after every C/C++ statement in output
131 • -i: suppress indentation of parameter declarations
133 • -o: suppress separation of declarations and statements
135 • -t: ignore temporary output irrespective of changes
137 • -x: omit indices, section names, table of contents
139 • +P: \input ctproofmac.tex instead of ctwimac.tex
141 • +lX/-lX: use macros for language X as of X{ctwimac|ctproofmac}.tex
143 • +s: print usage statistics
145 • --help: display help message and exit
147 • --version: output version information and exit
149
151 The environment variable CWEBINPUTS is used to search for the input
152 files, or the system default if CWEBINPUTS is not set. See tex(1) for
153 the details of the searching. To avoid conflicts with other programs
154 that also use the CWEBINPUTS environment, you can be more specific and
155 use CWEBINPUTS_cweb for special requirements in CWEB.
156 If prepared for NLS support, ctwill like ctangle and cweave uses the
158 environment variable TEXMFLOCALEDIR to configure the parent directory
159 where the “GNU gettext utilities” search for translation catalogs.
160 These variables are preconfigured in TeX Live’s texmf.cnf.
162
164 The location of the files mentioned below varies from system to system.
165 Use the kpsewhich utility to find their locations.
166 • ctwimac.tex: The default TeX macros \input in the first line of the
168 output file.
169 • ctproofmac.tex: If ctwill is invoked with the +P option, it will
171 change the first line of the output file to \input ctproofmac.tex.
172 In both cases you can request some prefix X with the +lX option, e.g.,
174 +ld will \input dctwimac.tex and +Pld will \input dctproofmac.tex. A
175 special application is the use of option +lpdf that will \input
176 pdfctwimac.tex for production of PDF output with active hyperlinks.
177 • webfile.bux: Reference definitions to resolve from other modules.
179 • system.bux: Reference definitions to resolve from C/C++ standard li‐
181 brary header files like <stdio.h>.
182 Other auxiliary files with references are created automatically by
184 ctwill and the actual index files are created by TeX.
185 • cwebman.tex: The CWEB user manual, available in PDF from CTAN
187 (https://ctan.org/pkg/cweb).
188
190 • The CWEB System of Structured Documentation: by Donald E. Knuth and
191 Silvio Levy (hardcopy version of cwebman.tex and the source code
192 listings of common.w, ctangle.w, and cweave.w).
193 • Digital Typography: by D. E. Knuth.
195 • Literate Programming: by D. E. Knuth.
197 • Weaving a Program: by Wayne Sewell.
199 cweb(1), tex(1), cc(1)
201
203 Don Knuth wrote ctwill based on cweave by Silvio Levy and Knuth.
204 ctwill and its utilities ctwill-refsort and ctwill-twinx have been ful‐
205 ly integrated with the CWEBbin extension that serves as the basis for
206 CWEB in TeX Live; see the project page (https://github.com/ascher‐
207 er/cwebbin).
208Web2c 2021 February 6, 2021 CTWILL(1)