Table 1.1 ANSI Predefined Macros

Macro Description
__DATE__ The compilation date of the current source file. The date is a string literal of the form Mmm dd yyyy. The month name Mmm is the same as for dates generated by the library function asctime declared in TIME.H.
__FILE__ The name of the current source file. __FILE__ expands to a string surrounded by double quotation marks.
__LINE__ The line number in the current source file. The line number is a decimal integer constant. It can be altered with a #line directive.
__STDC__ Indicates full conformance with the ANSI C standard. Defined as the integer constant 1 only if the /Za compiler option is given and you are not compiling C++ code; otherwise is undefined.
__TIME__ The most recent compilation time of the current source file. The time is a string literal of the form hh:mm:ss.
__TIMESTAMP__ The date and time of the last modification of the current source file, expressed as a string literal in the form Ddd Mmm Date hh:mm:ss yyyy, where Ddd is the abbreviated day of the week and Date is an integer from 1 to 31.




Table 1.2 Microsoft-Specific Predefined Macros

Macro Description
_CHAR_UNSIGNED Default char type is unsigned. Defined when /J is specified.
__cplusplus Defined for C++ programs only.
_CPPRTTI Defined for code compiled with /GR (Enable Run-Time Type Information).
_CPPUNWIND Defined for code compiled with /GX (Enable Exception Handling).
_DLL Defined when /MD or /MDd (Multithread DLL) is specified.
_M_ALPHA Defined for DEC ALPHA platforms. It is defined as 1 by the ALPHA compiler, and it is not defined if another compiler is used.
_M_IX86 Defined for x86 processors. See Table 1.3 for more details.
_M_MPPC Defined for Power Macintosh platforms. Default is 601 (/QP601). See Table 1.4 for more details.
_M_MRX000 Defined for MIPS platforms. Default is 4000 (/QMR4000). See Table 1.5 for more details.
_M_PPC Defined for PowerPC platforms. Default is 604 (/QP604). See Table 1.6 for more details.
_MFC_VER Defines the MFC version. Defined as 0x0421 for Microsoft Foundation Class Library 4.21. Always defined.
_MSC_EXTENSIONS This macro is defined when compiling with the /Ze compiler option (the default). Its value, when defined, is 1.
_MSC_VER Defines the compiler version. Defined as 1200 for Microsoft Visual C++ 6.0. Always defined.
_MT Defined when /MD or /MDd (Multithreaded DLL) or /MT or /MTd (Multithreaded) is specified.
_WIN32 Defined for applications for Win32®. Always defined.