A single-character constant in a preprocessor directive cannot have a negative value.

The ANSI standard header files are contained within the compiler itself and may be referred to in the way described in the standard (using, for example, #include <stdio.h>, etc.).

Quoted names for includable source files are supported. The compiler will accept host filenames or UNIX filenames. In the latter case, on non-UNIX hosts, the compiler tries to translate the filename to a local equivalent.

The recognized #pragma directives are shown in Pragmas.

The date and time of translation are always available, so __DATE__ and __TIME__ always give the date and time respectively.