@node Integer types
@chapter Integer types
@cpindex Integer types
@cpindex Types, integer
The C programming languages, provides several
integer types. All of these have limited
portability, and are intrinsic (they are
provided by the compiler, not the standard library.)
@table @code
@item char
@tpindex char
The smallest addressable unit of the machine
that can contain a basic character set.
It is either signed or unsigned, depending
on the implementation. It contains @code{CHAR_BIT}
bits. @sc{POSIX} requires that @code{CHAR_BIT == 8},
however the C standard only specifies that
@code{CHAR_BIT >= 8}.
@item signed char
@tpindex signed char
@iftex
Signed version of @code{char}. It is guaranteed
to have a range of either
[@math{-2}@sup{@code{CHAR_BIT}@math{~-~1}}@math{~+~1},
@math{2}@sup{@code{CHAR_BIT}@math{~-~1}}@math{~-~1}]
or
[@math{-2}@sup{@code{CHAR_BIT}@math{~-~1}},
@math{2}@sup{@code{CHAR_BIT}@math{~-~1}}@math{~-~1}].
@end iftex
@ifnottex
Signed version of @code{char}. It is
guaranteed to have a range of at least either
[-2^(@code{CHAR_BIT} - 1) + 1, 2^(@code{CHAR_BIT} - 1) - 1] or
[-2^(@code{CHAR_BIT} - 1), 2^(@code{CHAR_BIT} - 1) - 1].
@end ifnottex
@item unsigned char
@tpindex unsigned char
Unsigned version of @code{char}. It is guaranteed
to have a range of exactly
[0, @math{2}@sup{@code{CHAR_BIT}}@math{~-~1}].
@item short int
@itemx short
@itemx signed short int
@itemx signed short
@tpindex short int
@tpindex signed short int
Signed integer type of at least 16 bits. Its range is
guaranteed contain at least [@math{-32767}, @math{32767}].
@itemx unsigned short int
@itemx unsigned short
@tpindex unsigned short int
Unsigned integer type of at least 16 bits. Its range is
guaranteed contain at least [0, @math{65535}].
@item signed int
@itemx int
@tpindex int
@tpindex signed int
Signed integer type of at least 16 bits. Its range is
guaranteed contain at least [@math{-32767}, @math{32767}].
@item unsigned int
@tpindex unsigned int
Unsigned integer type of at least 16 bits. Its range is
guaranteed contain at least [0, @math{65535}].
@item signed
@tpindex signed
Alias for @code{signed int} which is used when the
valid value range is the least guaranteed range. Thus
The range may exceed [@math{-32767}, @math{32767}],
but values outside that range [[@math{-32767},
@math{32767}]] should not be used.
@item unsigned
@tpindex unsigned
Alias for @code{unsigned int} which is used when the
valid value range is the least guaranteed range. Thus
The range may exceed [0, @math{65535}], but values
outside that range [[0, @math{65535}]] should not be used.
@item long int
@itemx long
@itemx signed long int
@itemx signed long
@tpindex signed long int
@tpindex long int
Signed integer type of at least 32 bits. Its range is
guaranteed contain at least [@math{-2147483647},
@math{2147483647}].
@item unsigned long int
@itemx unsigned long
@tpindex unsigned long int
Unsigned integer type of at least 32 bits. Its range is
guaranteed contain at least [0, @math{4294967295}].
@item long long int
@itemx long long
@itemx signed long long int
@itemx signed long long
@tpindex long long int
@tpindex signed long long int
Signed integer type of at least 64 bits. Its range is
guaranteed contain at least [@math{-9223372036854775807},
@math{9223372036854775807}]. This type was added in C99.
@item unsigned long long int
@itemx unsigned long long
@tpindex unsigned long long int
Unsigned integer type of at least 64 bits. Its range is
guaranteed contain at least [0, @math{18446744073709551615}].
This type was added in C99.
@end table
