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Data Type Constants

 

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Data type constants are implementation-dependent ranges of values allowed for integral data types. The constants listed below give the ranges for the integral data types and are defined in LIMITS.H.

Note

The /J compiler option changes the default char type to unsigned.

Constant Value Meaning
SCHAR_MAX 127 Maximum signed char value
SCHAR_MIN –128 Minimum signed char value
UCHAR_MAX 255 (0xff) Maximum unsigned char value
CHAR_BIT 8 Number of bits in a char
USHRT_MAX 65535 (0xffff) Maximum unsigned short value
SHRT_MAX 32767 Maximum (signed) short value
SHRT_MIN –32768 Minimum (signed) short value
UINT_MAX 4294967295 (0xffffffff) Maximum unsigned int value
ULONG_MAX 4294967295 (0xffffffff) Maximum unsigned long value
INT_MAX 2147483647 Maximum (signed) int value
INT_MIN –2147483647–1 Minimum (signed) int value
LONG_MAX 2147483647 Maximum (signed) long value
LONG_MIN –2147483647–1 Minimum (signed) long value
CHAR_MAX 127 (255 if /J option used) Maximum char value
CHAR_MIN –128 (0 if /J option used) Minimum char value
MB_LEN_MAX 2 Maximum number of bytes in multibyte char
_I64_MAX 9223372036854775807 Maximum (signed) __int64 value
_I64_MIN -9223372036854775807-1 Minimum (signed) __int64 value
_UI64_MAX 0xffffffffffffffff Maximum (unsigned) __int64 value

The following constants give the range and other characteristics of the double and float data types, and are defined in FLOAT.H:

Constant Value Description
DBL_DIG 15 # of decimal digits of precision
DBL_EPSILON 2.2204460492503131e-016 Smallest such that 1.0+DBL_EPSILON !=1.0
DBL_MANT_DIG 53 # of bits in mantissa
DBL_MAX 1.7976931348623158e+308 Maximum value
DBL_MAX_10_EXP 308 Maximum decimal exponent
DBL_MAX_EXP 1024 Maximum binary exponent
DBL_MIN 2.2250738585072014e-308 Minimum positive value
DBL_MIN_10_EXP (-307) Minimum decimal exponent
DBL_MIN_EXP (–1021) Minimum binary exponent
_DBL_RADIX 2 Exponent radix
_DBL_ROUNDS 1 Addition rounding: near
FLT_DIG 6 Number of decimal digits of precision
FLT_EPSILON 1.192092896e-07F Smallest such that 1.0+FLT_EPSILON !=1.0
FLT_MANT_DIG 24 Number of bits in mantissa
FLT_MAX 3.402823466e+38F Maximum value
FLT_MAX_10_EXP 38 Maximum decimal exponent
FLT_MAX_EXP 128 Maximum binary exponent
FLT_MIN 1.175494351e-38F Minimum positive value
FLT_MIN_10_EXP (–37) Minimum decimal exponent
FLT_MIN_EXP (–125) Minimum binary exponent
FLT_RADIX 2 Exponent radix
FLT_ROUNDS 1 Addition rounding: near

See Also

Global Constants