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): add
dir
to the search for
unhandled troff command .CW
directives.
-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,
or in the environment variable
include.
Without this option,
/$objtype/include
and
/sys/include
are used as the last two searched directories for include directives,
where
$objtype
is read from the environment.
-V
Print extra debugging information.
-P
Do not insert
“#line”
directives into the output.
-.
Inhibit include search in the source’s directory.
-i
Print the list of directories searched when
#include
is found.
Last listed are searched first.
In the absence of the
-P
option, the processed text output is sprinkled
with lines that show the original input line numbering:
#line
linenumber
"ifile"
The command reads the environment variable
include
and adds its (blank-separated) list of directories to
the standard search path for
unhandled troff command .CW
directives. They are looked at before any directories specified with
-I,
which are looked at before the default directories.
The input language is as described in the ANSI C standard.
The standard Plan 9 C compilers do not use
cpp;
they contain their own simple but adequate preprocessor, so
cpp
is usually superfluous.
FILES
/sys/include
directory for machine-independent include files
/$objtype/include
directory for machine-dependent include files
SOURCE
/sys/src/cmd/cpp
SEE
2c(1)