C Programming

Within a translation unit, all declarations of the same object or function identifier with internal linkage refer to the same thing, and the object or function is unique to that translation unit. All declarations for the same object or function identifier with external linkage refer to the same thing, and the object or function is shared by the entire program. (more…)

A preprocessor performs macro substitution, conditional compilation, and inclusion of named files. Lines beginning with #, perhaps preceded by white space, communicate with this preprocessor. The syntax of these lines is independent of the rest of the language; they may appear anywhere and have effect that lasts (independent of scope) until the end of the translation unit. (more…)

The character set of C source programs is contained within seven-bit ASCII, but is a superset of the ISO 646-1983 Invariant Code Set. In order to enable programs to be represented in the reduced set, all occurrences of the following trigraph sequences are replaced by the corresponding single character. This replacement occurs before any other processing. (more…)

Lines that end with the backslash character \ are folded by deleting the backslash and the following newline character. This occurs before division into tokens.