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

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

ctangle [ -bhp ] [ +s ] webfile[.w] [changefile[.ch]] [outputfile[.c]]
cweave [ -befhpx ] [ +s ] webfile[.w] [changefile[.ch]] [output‐

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 informa‐
tion that it gathers automatically.

CWEB allows you to prepare a single document containing all the infor‐
mation 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

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.

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

TeX macros used by cweave output.

The user manual.

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 cweb‐
man.tex and the source code listings)

tex(1), cc(1)

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 refine‐
ments. Many other helpers are acknowledged in the CWEB manual.

Web2C 2009 19 December 2004 CWEB(1)