CPP(1)                                                     CPP(1)

     NAME
          cpp - C language preprocessor

     SYNOPSIS
          cpp [ option ... ] [ ifile [ ofile ] ]

     DESCRIPTION
          Cpp interprets ANSI C preprocessor directives and does macro
          substitution.  The input ifile and output ofile default to
          standard input and standard output respectively.

          The options are:

          -Dname
          -Dname=def
          -Idir
               Same as in 2c(1).

          -M   Generate no output except a list of include files in a
               form suitable for specifying dependencies to mk(1). Use
               twice to list files in angle brackets.

          -N   Turn off default include directories.  All must be
               specified with -I.  Without this option,
               /$objtype/include and /sys/include are used as the last
               two searched directories for include directives, where
               $objtype is read from the environment.

          -V   Print extra debugging information.

          -+   Understand C++ comments.

          The output file contains processed text sprinkled with lines
          that show the original input line numbering:

               #line linenumber "ifile"

          The input language is as described in the ANSI C standard.
          The C compilers do not use cpp; they contain their own sim-
          ple but adequate preprocessor, so cpp is usually superflu-
          ous.

     FILES
          /sys/include      directory for machine-independent include
                            files
          /$objtype/include directory for machine-dependent include
                            files

     SOURCE
          /sys/src/cmd/cpp

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     CPP(1)                                                     CPP(1)

     SEE ALSO
          2c(1)

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