V8/usr/man/man8/cpp.8

.TH CPP 8
.SH NAME
cpp \- C language preprocessor
.SH SYNOPSIS
.B /lib/cpp [
option ...
.B ]
.B [
ifile
.B [
ofile
.B ] ]
.SH DESCRIPTION
.I Cpp\^
interprets control lines (marked with `#') for
.IR cc (1)
and other compilers.
The input,
.I ifile,
and output,
.I ofile,
default to standard input and standard output respectively.
.PP
The options are:
.TP
.B \-P
Do not place `#line' indications on the output.
.TP
.B \-C
Do not remove comments.
.TP
.BI \-U name\^
.PD 0
.TP
.BI \-D name\^
.TP
.BI \-D name=def\^
.TP
.BI \-I dir\^
Same as in
.IR cc (1).
.B \-U 
overrides
.BR \-D .
.PD
.TP
.B \-M
Pass modification date with file names, in the form \fIfile@modtime\fP,
where modtime is the integer number of seconds since the epoch.
.TP
.B \-T
Truncate preprocessor symbols to eight characters.
.PP
The name
`_\^\^_\s-1LINE\s+1_\^\^_'
is the current line number in the input file,
`_\^\^_\s-1FILE\s+1_\^\^_'
is the file name.
The line number and (optionally) the file name may be set by
.IP
.B #line
.I integer-constant
.BI """ filename """
.LP
These symbols are also predefined in various implementations:
.PD 0
.RS 
.TP "\w'UNIX system: 'u"
operating system:
ibm, gcos, os, tss, unix
.TP
hardware:
interdata, pdp11, u370, u3b, u3b5, vax
.TP
\s-1UNIX\s+1 system:
.SM RES\*S,
.SM RT
.TP
\fIlint\fR(1):
lint
.RE
.PD
.PP
Any number of blanks and tabs are allowed between the
initial `#' and the control directive.
.PP
A builtin function
.RI `defined( name )'
or
.RI `defined " name" '
may be used in constant expressions within a
.B #if
control lines to test whether
.I name
is defined.
.PP
Preprocessor formal parameters are recognized withing
quoted strings in the replacement text.
When comments are removed, they are replaced by null strings;
this unofficial feature makes it possible to construct
identifiers by concatenation.
.SH FILES
/usr/include	standard directory for include files