WEB(1L)

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

SYNOPSIS
ctangle [ -bhp ] [ +s ] webfile[.w] [changefile[.ch]]
cweave [ -bfhpx ] [ +s ] webfile[.w] [changefile[.ch]]

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 either one or two 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. 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.

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 shows a banner line on your terminal. The -h option shows a happy message if the processing was successful. The -p option shows 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 two other options applicable to cweave only: -f means do not force a newline after every statement in the formatted output. -x means omit the index and table of contents.

The output C and TeX file names are formed by using .c and .tex as extensions of the WEB file name.

FILES
/usr/lib/tex/macros/cwebmac.tex TeX macros used by cweave output.
/usr/local/src/cweb/webman.tex The user manual.
/usr/local/src/cweb/examples/wc.x An introductory example.

SEE ALSO
Literate Programming by D.E. Knuth.
Weaving a Program by Wayne Sewell
tex(1), cc(1), web(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.