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(libc.info)Range of Type

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Range of an Integer Type
------------------------

   Suppose you need to store an integer value which can range from zero
to one million.  Which is the smallest type you can use?  There is no
general rule; it depends on the C compiler and target machine.  You can
use the `MIN' and `MAX' macros in `limits.h' to determine which type
will work.

   Each signed integer type has a pair of macros which give the smallest
and largest values that it can hold.  Each unsigned integer type has one
such macro, for the maximum value; the minimum value is, of course,
zero.

   The values of these macros are all integer constant expressions.  The
`MAX' and `MIN' macros for `char' and `short int' types have values of
type `int'.  The `MAX' and `MIN' macros for the other types have values
of the same type described by the macro--thus, `ULONG_MAX' has type
`unsigned long int'.

`SCHAR_MIN'
     This is the minimum value that can be represented by a
     `signed char'.

`SCHAR_MAX'
`UCHAR_MAX'
     These are the maximum values that can be represented by a
     `signed char' and `unsigned char', respectively.

`CHAR_MIN'
     This is the minimum value that can be represented by a `char'.
     It's equal to `SCHAR_MIN' if `char' is signed, or zero otherwise.

`CHAR_MAX'
     This is the maximum value that can be represented by a `char'.
     It's equal to `SCHAR_MAX' if `char' is signed, or `UCHAR_MAX'
     otherwise.

`SHRT_MIN'
     This is the minimum value that can be represented by a
     `signed short int'.  On most machines that the GNU C library runs
     on, `short' integers are 16-bit quantities.

`SHRT_MAX'
`USHRT_MAX'
     These are the maximum values that can be represented by a
     `signed short int' and `unsigned short int', respectively.

`INT_MIN'
     This is the minimum value that can be represented by a
     `signed int'.  On most machines that the GNU C system runs on, an
     `int' is a 32-bit quantity.

`INT_MAX'
`UINT_MAX'
     These are the maximum values that can be represented by,
     respectively, the type `signed int' and the type `unsigned int'.

`LONG_MIN'
     This is the minimum value that can be represented by a
     `signed long int'.  On most machines that the GNU C system runs
     on, `long' integers are 32-bit quantities, the same size as `int'.

`LONG_MAX'
`ULONG_MAX'
     These are the maximum values that can be represented by a
     `signed long int' and `unsigned long int', respectively.

`LONG_LONG_MIN'
     This is the minimum value that can be represented by a
     `signed long long int'.  On most machines that the GNU C system
     runs on, `long long' integers are 64-bit quantities.

`LONG_LONG_MAX'
`ULONG_LONG_MAX'
     These are the maximum values that can be represented by a `signed
     long long int' and `unsigned long long int', respectively.

`WCHAR_MAX'
     This is the maximum value that can be represented by a `wchar_t'.
     Note: Extended Char Intro.

   The header file `limits.h' also defines some additional constants
that parameterize various operating system and file system limits.
These constants are described in Note: System Configuration.