__LINE__ |
The current line number. |
__DATE__ |
The date of translation of the source file. |
__TIME__ |
The time of translation of the source file. |
__STDC__ |
Indicates a conforming implementation. |
__FILE__ |
The current file name. |
__STR__ |
Indicates the
compiler will generate inline code for certain string functions (as
defined in
/usr/include/string.h). |
__MATH__ |
Indicates the
compiler will generate inline code for certain math functions (as defined
in
/usr/include/math.h). |
__ANSI__ |
Indicates langlvl is set equal to ANSI. |
__SAA__ |
Indicates langlvl is set equal to SAA. |
__SAA_L2__ |
Indicates langlvl is set equal to SAAL2. |
__EXTENDED__ |
Indicates langlvl is set equal to extended. |
__TIMESTAMP__ |
Indicates the date and time when the source file was last
modified. |
#define Name
TokenString |
Replaces subsequent instances of Name with
TokenString. |
#define Name(Argument,...,Argument) TokenString |
Replaces subsequent instances of the sequence Name
(Argument, . . . ,Argument) with
TokenString, where each occurrence of an Argument in
TokenString is replaced by the corresponding token in the
comma-separated list. Note that there must not be any space between
Name and the left parenthesis. |
#undef Name |
Ignores the definition of Name from this point on. |
#include
"File" or #include <File> |
Includes at this point the contents of File, which cpp
then processes.
If you enclose File in " " (double
quotation marks) the cpp command searches first in the directory of
InFile, second in directories named with the -I flag, and
last in directories on a standard list.
If you use the <File> notation,
the cpp command searches for File only in the standard
directories. It does not search the directory in which InFile
resides. |
#line Number
["File"] |
Causes the implementation to behave as if the
following sequence of source lines begins with a source line that has a
line number as specified by Number. If File is supplied, the
presumed name of the file is changed to be File. |
#error TokenString |
Produces a diagnostic message that includes
TokenString. |
#pragma TokenString |
An implementation-defined instruction to the compiler. |
#endif |
Ends a section of lines begun by a test directive
(#if, #ifdef, or #ifndef). Each test directive must
have a matching #endif. |
#ifdef Name |
Places the subsequent lines in the output only if:
Name has been defined by a previous
#define
OR
Name has been defined by the
-D flag,
OR
Name is a special name recognized
by the
cpp command,
AND
Name has not been undefined by an
intervening
#undef,
OR
Name has not been undefined with
the -U
flag. |
#ifndef Name |
Places the subsequent lines in the output only if:
Name has never been defined by a
previous
#define,
AND
Name is not a special name
recognized by the
cpp command,
OR
Name has been defined by a
previous
#define but it has been undefined by an intervening #undef,
OR
Name is a special name recognized
by the
cpp command, but it has been undefined with the -U flag. |
#if Expression |
Places subsequent lines in the output only if Expression
evaluates to nonzero. All the binary nonassignment C operators, the ?:
operator, and the unary -, !, and - operators are legal in
Expression. The precedence of the operators is the same as that
defined in the C Language. There is also a unary operator
defined, which can be used in Expression in these two forms:
- defined
(Name) or
defined Name
- This allows the utility of #ifdef and #ifndef in a
#if directive. Only these operators, integer constants, and names
that are known by cpp should be used in Expression. The
sizeof operator is not available.
|
#elif Expression |
Places subsequent lines in the output only if the expression in
the preceding #if or #elif directive evaluates to false or
is undefined, and this Expression evaluates to true. |
#else |
Places subsequent lines in the output only if the expression in
the preceding #if or #elif directive evaluates to false or
is undefined (and hence the lines following the #if and preceding
the #else have been ignored).
Each test directive's condition is
checked in order. If it evaluates to false (0), the group that it controls
is skipped. Directives are processed only through the name that determines
the directive in order to keep track of the level of nested conditionals;
the rest of the directives' preprocessing tokens are ignored, as are the
other preprocessing tokens in the group. Only the first group whose
control condition evaluates to true (nonzero) is processed. If none of the
conditions evaluates to true, and there is a #else directive, the
group controlled by the #else is processed; lacking a #else
directive, all the groups until the #endif are skipped. |
-C |
Copies C language comments from the source file to the output
file. If you
omit this flag, the cpp command removes all C language comments
except those
found on a cpp directive line. |
-DName[=Definition] |
Defines Name as in a #define directive. The
default
Definition is 1. |
-IDirectory |
Looks first in Directory, then looks in the directories
on the
standard list for #include files with names that do not begin with
a / (slash).
See the previous discussion of #include. |
-P |
Preprocesses input without producing line control information
for the next
pass of the C compiler. |
-qDBCS |
Specifies double-byte character set mode. |
-UName |
Removes any initial definition of Name, where
Name is a
symbol predefined by the preprocessor (except for the four preprocessor
mode
indicators: __ANSI__, __EXTENDED__, __SAA__, and
__SAA_L2__). This flag is not recognized in ANSI mode. |
-qlanglvl=Language |
Selects a language level for processing. Language can be
ANSI, SAA,
SAAL2, or extended. The default is extended.
Note: When Language is
extended,
_NO_PROTO is not automatically defined. Such definition can be done using
the -D option in the /etc/xlc.cfg file.
|