1. Identifiers may only include the following characters: letters ('a'..'z', 'A'..'Z'), digits ('0'..'9') and underscores ('_'). C is case sensitive, so seaside, SeaSide and SEASIDE are distinct identifiers.
2. The first character must not be a digit.
3. The identifier must not be one of C's 32 keywords.
auto break case char
const continue default do
double else enum extern
float for goto if
int long register return
short signed sizeof static
struct switch typedef union
unsigned void volatile while
David C. Hamill
D.Hamill@surrey.ac.uk