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Constants

Integer constants do not contain a decimal point. They are of the smallest type that would hold them unless they have a U or L suffix letter:

nnn	signed short int	if between -32768 and 32767
nnnU	unsigned short int	if between 0 and 32767
nnn	unsigned short int	if between 32768 and 65535
nnn	signed long int	if greater than -32768 or 65535
nnnL	signed long int

Octal constants have an "0" prefix: 0nnn

Hexadecimal constants have an "0x" prefix: 0xnn

Floating point constants contain a decimal point, have an exponent, or have an F suffix letter. They are of type double unless they have an F or L suffix letter:

nnF	float
nn.nn[Enn]F	float
nn.nn[Enn]	double
nn.nn[Enn]L	long double

Character constants are enclosed in single quotes: 'c'. The compiler will substitute the appropriate character if any of the following "backslash" or "escape" codes are used:

\a	Alert (bell)
\b	Backspace
\f	Form feed
\n	Newline
\r	Carriage return
\t	Horizontal tab
\v	Vertical tab
\'	Single quote
\"	Double quote
\\	Backslash
\0	Null
\nnn	ASCII code in octal (a maximum of three digits are recognised)
\xnn	ASCII code in hexadecimal

String constants are enclosed in double quotes: "string". The compiler automatically appends a null character to the end of the string.

Last updated 10th October 2002, Peter Dziwior.