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.