6.7.2 Encoding Variations

The encoding schemes fall into two camps. The first is one in which each multibyte character is self-identifying, that is, any multibyte character can simply be inserted between any pair of multibyte characters.

The second scheme is one in which the presence of special shift bytes changes the interpretation of subsequent bytes. An example is the method used by some character terminals to get in and out of line-drawing mode. For programs written in multibyte characters with a shift-state-dependent encoding, ISO C requires that each comment, string literal, character constant, and header name must both begin and end in the unshifted state.