NAME

       ctwill,  ctwill-proofsort, ctwill-refsort, ctwill-twinx - translate CWEB to TeX with mini-
       indexes

SYNOPSIS

       ctwill [options] webfile[.w] [{changefile[.ch]|-} [outfile[.tex]]]
       ( ctwill-proofsort < texfile.tex ) 1<> texfile.tex
       ctwill-refsort < indexfile.ref > indexfile.sref
       ctwill-twinx outfile.tex [outfile.tex ...]  > index.tex

DESCRIPTION

       The ctwill program converts a CWEB source document into a TeX file that may  be  formatted
       and  printed in the usual way.  It takes appropriate care of typographic details like page
       layout and the use of indentation, italics, boldface,  etc.,  and  it  supplies  extensive
       cross-index information that it gathers automatically.

       CWEB allows you to prepare a single document containing all the information that is needed
       both to produce a compilable  C/C++ program  and  to  produce  a  well-formatted  document
       describing the program in as much detail as the writer may desire.  The user of CWEB ought
       to be familiar with TeX as well as C/C++.

USAGE

       The command line should have one, two, or three names on it.  The first is  taken  as  the
       CWEB input file (and .w is added if there is no extension).  If there is a second name, it
       is a change file (and .ch is added if there is no extension).  The change  file  overrides
       parts  of  the CWEB file, as described in the documentation.  If there is a third name, it
       overrides the default name of the output file, which is ordinarily the same as the name of
       the  input  file (but on the current directory) with the extension .tex.  If you just want
       to change the output file name, but don’t have a change file to apply, you can use `-'  as
       the second argument.

       ctwill is exactly like cweave except that it produces much better documentation, for which
       you must work much harder.  You should run ctwill twice, once to prime the pump  and  once
       to get decent answers.  Moreover, you must run the output twice through TeX.

       After  tex foo you will have output that looks like final pages except that the entries of
       mini-indexes won’t be alphabetized.  The first run produces a weird file  called  foo.ref.
       Say ctwill-refsort < foo.ref > foo.sref and then another tex foo will produce alphabetized
       output.

       The ctwill-twinx program compiles a master index for a set of related programs  that  have
       been  processed  by  ctwill  (not  by  cweave, mind you!).  The individual programs should
       define their names with a line  of  the  form  \def\title{NAME}.   For  your  convenience,
       ctwill-twinx  grabs  the  first  “word”  in  \title and turns it into uppercase form.  You
       should adapt file twinx-startup.tex for the first page of the master index.

       The mini-indexes list identifiers that are used but not defined on each  two-page  spread.
       At  the  end  of each section, ctwill gives TeX a list of identifiers used in that section
       and information about where they are defined.

       The current meaning of every identifier is initially \uninitialized.   Then  ctwill  reads
       the .aux file for your job, if any.

       Before  reading  the  .aux file, ctwill actually looks for a file called system.bux, which
       will be read if present.  And after foo.aux, a third possibility is foo.bux.  The  general
       convention  is to put definitions of system procedures such as printf into system.bux, and
       to put definitions found in specifically foo-ish header files into foo.bux.  Like the .aux
       files, .bux files should contain only @$ specifications.

       The meaning specified by @$...@> generally has four components: an identifier (followed by
       space), a program name (enclosed in braces), a section number (followed by space),  and  a
       TeX part.

       A  special  proofmode  is provided so that you can check ctwill’s conclusions about cross-
       references.  Run ctwill with the flag +P, and  TeX  will  produce  a  specially  formatted
       document   with   mini-indexes  for  each  section,  so  that  you  can  check  that  your
       specifications are correct.

       This proofmode format is used in conjunction with pdfctproofmac.tex  that  creates  active
       hyperlinks  in PDF and HINT output.  You can use ctwill-proofsort to get the index entries
       in alphabetical order; just invoke

       ( ctwill-proofsort < texfile.tex ) 1<> texfile.tex

       after invoking ctwill (twice), but before invoking TeX (once).

       More details how to use ctwill can be found in the first  sections  of  its  source  code,
       respectively the change file cweav-twill.ch applicable to the cweave.w source.  A complete
       example with all bells and whistles is described in Mini-Indexes  for  Literate  Programs,
       pages 225–245 of Knuth’s Digital Typography (CSLI, 1999).

DIFFERENCES TO ORIGINAL CTWILL

       The present incarnation of ctwill and its utilities tries hard to be a drop-in replacement
       for the original package.  There are, however, a few differences worth noting:

       • This version is based on the most recent version of CWEB (4.11).

       • In TeX Live the utility programs are prefixed with ctwill- and the macro files  with  ct
         for technical reasons.

       • Options  --help, --quiet, --verbose, --version, and flags +c, -i, -o, and +lX are new in
         CWEBbin and TeX Live.

       • Option +lX is accompanied by example wrapper files for  ctwimac.tex  and  ctproofmac.tex
         with translated captions for German (+ld).

       • Option  +lX  is also accompanied by an extended pdfctwimac.tex for production of PDF and
         HINT output with active hyperlinks (+lpdf).

       • ctwill in TeX Live operates silently by default; use the --verbose  option  to  get  the
         original behavior.

       • File  lookup  with  the  environment  variable CWEBINPUTS is extended to permit several,
         colon-separated, paths; see ENVIRONMENT below.

       • If properly configured, the main program ctwill  is  localized  with  the  “GNU  gettext
         utilities”.

OPTIONS

       Options  on the command line may be either turned off with `-' (if they are on by default)
       or turned on with `+' (if they are off by default).  In fact, the  options  are  processed
       from  left  to  right, so a sequence like --verbose -h will only show the banner line (+b)
       and the progress report (+p), but leave out the happy message (-h).

       • +b: print banner line on terminal

       • +h: print success message on completion

       • +p: print progress report messages

       • +q/-q: shortcut for -bhp; also --quiet (default)

       • +v/-v: shortcut for +bhp; also --verbose

       • +c: check temporary output for changes

       • -e: do not enclose C/C++ material in \PB{...}

       • -f: do not force a newline after every C/C++ statement in output

       • -F: do not force a compound statement to start on a new line

       • -i: suppress indentation of parameter declarations

       • -o: suppress separation of declarations and statements

       • -x: omit indices, section names, table of contents

       • +P: \input ctproofmac.tex instead of ctwimac.tex

       • +lX/-lX: use macros for language X as of X{ctwimac|ctproofmac}.tex

       • +s: print usage statistics

       • +t: treat typename in a template like typedef

       • --help: display help message and exit

       • --version: output version information and exit

ENVIRONMENT

       The environment variable CWEBINPUTS is used to search for the input files, or  the  system
       default  if CWEBINPUTS is not set.  See tex(1) for the details of the searching.  To avoid
       conflicts with other programs that also use the CWEBINPUTS environment, you  can  be  more
       specific and use CWEBINPUTS_cweb for special requirements in CWEB.

       If  prepared for NLS support, ctwill like ctangle and cweave uses the environment variable
       TEXMFLOCALEDIR to configure the parent directory where the “GNU gettext utilities”  search
       for translation catalogs.

       These variables are preconfigured in TeX Live’s texmf.cnf.

FILES

       The location of the files mentioned below varies from system to system.  Use the kpsewhich
       utility to find their locations.

       • ctwimac.tex: The default TeX macros \input in the first line of the output file.

       • ctproofmac.tex: If ctwill is invoked with the +P option, it will change the  first  line
         of the output file to \input ctproofmac.tex.

       In  both  cases  you  can request some prefix X with the +lX option, e.g., +ld will \input
       dctwimac.tex and +Pld will \input dctproofmac.tex.  A special application is  the  use  of
       option +lpdf that will \input pdfctwimac.tex or \input pdfctproofmac.tex for production of
       PDF and HINT output with active hyperlinks.

       • webfile.bux: Reference definitions to resolve from other modules.

       • system.bux: Reference definitions to resolve from C/C++ standard  library  header  files
         like <stdio.h>.

       Other  auxiliary  files with references are created automatically by ctwill and the actual
       index files are created by TeX.

       • cwebman.tex:    The    CWEB    user    manual,    available    in    PDF    from    CTAN
         ⟨https://ctan.org/pkg/cweb⟩.

SEE ALSO

       • The  CWEB  System  of  Structured  Documentation:  by  Donald  E. Knuth  and Silvio Levy
         (hardcopy version of cwebman.tex and the source code listings  of  common.w,  ctangle.w,
         and cweave.w).

       • Digital Typography: by D. E. Knuth (CSLI, 1999).

       • Literate Programming: by D. E. Knuth (CSLI, 1992).

       • Weaving a Program: by Wayne Sewell.

       cweb(1), tex(1), cc(1)

AUTHORS

       Don Knuth wrote ctwill based on cweave by Silvio Levy and Knuth.
       Contemporary development on https://github.com/ascherer/cwebbin.