cweb(1)

NAME

   ctangle, cweave - translate CWEB to C and/or TeX

SYNOPSIS

   ctangle [-bhp] [+s] webfile[.w] [{changefile[.ch]|-} [outfile[.c]]]
   cweave [-befhpx] [+s] webfile[.w] [{changefile[.ch]|-} [outfile[.tex]]]

DESCRIPTION

   The  ctangle  program  converts a CWEB source document into a C program
   that may be compiled in the usual way.  The output file includes  #line
   specifications  so  that  debugging  can  be  done in terms of the CWEB
   source file.

   The cweave program converts the same CWEB file 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 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.

   The command line should have one, two, or three names on it.  The first
   is  taken  as the CWEB file (and .w is added if there is no extension).
   If that file cannot be opened, the extension  .web  is  tried  instead.
   (But  .w  is recommended, since .web usually implies Pascal.)  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 WEB 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 .c or .tex.

   Options  in  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 -f +f corresponds to +f (which is the default).

   The -b option suppresses the banner line that normally appears on  your
   terminal  when  ctangle or cweave begins.  The -h option suppresses the
   happy message that normally appears if the processing  was  successful.
   The  -p  option suppresses progress reports (starred module numbers) as
   the processing takes place.  If you say -bhp, you get nothing but error
   messages.

   The  +s option prints statistics about memory usage at the end of a run
   (assuming that the programs have been compiled with the -DSTAT switch).

   There are three other options applicable to cweave only:  -f  means  do
   not  force a newline after every statement in the formatted output.  -e
   inhibits the enclosure of C material formatted by  cweave  in  brackets
   \PB{...}.   Such  brackets  are normally inserted so that special hooks
   can be used by cweb-latex and similar  programs.   -x  means  omit  the
   index and table of contents.

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.

FILES

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

   cwebmac.tex
          TeX macros used by cweave output.

   cwebman.tex
          The user manual.

SEE ALSO

   Literate Programming
          by D. E. Knuth.

   Weaving a Program
          by Wayne Sewell.

   The CWEB System of Structured Documentation
          by  Donald  E.  Knuth  and  Silvio  Levy  (hardcopy  version  of
          cwebman.tex and the source code listings).

   tex(1), cc(1).

AUTHORS

   Don  Knuth  wrote  WEB  for  TeX  and Pascal.  Silvio Levy designed and
   developed CWEB by adapting the WEB conventions  to C  and  by  recoding
   everything   in   CWEB.   Knuth  began  using  CWEB  and  made  further
   refinements.  Many other helpers are acknowledged in the CWEB manual.

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