PROP_NUMBER(3)

NAME
prop_number, prop_number_create_integer, prop_number_create_unsigned_integer, prop_number_copy, prop_number_size, prop_number_unsigned, prop_number_integer_value, prop_number_unsigned_integer_value, prop_number_equals, prop_number_equals_integer, prop_number_equals_unsigned_integer - numeric value property object

LIBRARY
libprop

SYNOPSIS
#include <prop/proplib.h>
prop_number_t
prop_number_create_integer(int64_t val);
prop_number_t
prop_number_create_unsigned_integer(uint64_t val);
prop_number_t
prop_number_copy(prop_number_t number);
int
prop_number_size(prop_number_t number);
bool
prop_number_unsigned(prop_number_t number);
int64_t
prop_number_integer_value(prop_number_t number);
uint64_t
prop_number_unsigned_integer_value(prop_number_t number);
bool
prop_number_equals(prop_number_t num1, prop_number_t num2);
bool
prop_number_equals_integer(prop_number_t number, int64_t val);
bool
prop_number_equals_unsigned_integer(prop_number_t number, uint64_t val);

DESCRIPTION
The prop_number family of functions operate on a numeric value property object type. Values are either signed or unsigned, and promoted to a 64-bit type (int64_t or uint64_t, respectively).

It is possible to compare number objects that differ in sign. Such comparisons first test to see if each object is within the valid number range of the other:

•   Signed numbers that are greater than or equal to 0 can be compared to unsigned numbers.

•   Unsigned numbers that are less than or equal to the largest signed 64-bit value (INT64_MAX) can be compared to signed numbers.

Number objects have a different externalized representation depending on their sign:

•   Signed numbers are externalized in base-10 (decimal).

•   Unsigned numbers are externalized in base-16 (hexadecimal).

When numbers are internalized, the sign of the resulting number object (and thus its valid range) is determined by a set of rules evaluated in the following order:

•   If the first character of the number is a ‘-’ then the number is signed.

•   If the first two characters of the number are ‘0x’ then the number is unsigned.

•   If the number value fits into the range of a signed number then the number is signed.

•   In all other cases, the number is unsigned.

prop_number_create_integer(int64_t val)
    Create a numeric value object with the signed value val. Returns NULL on failure.

prop_number_create_unsigned_integer(uint64_t val)
    Create a numeric value object with the unsigned value val. Returns NULL on failure.

prop_number_copy(prop_number_t number)
    Copy a numeric value object. If the supplied object isn't a numeric value, NULL is returned.

prop_number_size(prop_number_t number)
    Returns 8, 16, 32, or 64, representing the number of bits required to hold the value of the object. If the supplied object isn't a numeric value, NULL is returned.

prop_number_unsigned(prop_number_t number)
    Returns true if the numeric value object has an unsigned value.

prop_number_integer_value(prop_number_t number)
    Returns the signed integer value of the numeric value object. If the supplied object isn't a numeric value, zero is returned. Thus, it is not possible to distinguish between “not a prop_number_t” and “prop_number_t has a value of 0”.

prop_number_unsigned_integer_value(prop_number_t number)
    Returns the unsigned integer value of the numeric value object. If the supplied object isn't a numeric value, zero is returned. Thus, it is not possible to distinguish between “not a prop_number_t” and “prop_number_t has a value of 0”.

prop_number_equals(prop_number_t num1, prop_number_t num2)
    Returns true if the two numeric value objects are equivalent. If at least one of the supplied objects isn't a numeric value, false is returned.

prop_number_equals_integer(prop_number_t number, int64_t val)
    Returns true if the object's value is equivalent to the signed value val. If the supplied object isn't a numerical value or if val exceeds INT64_MAX, false is returned.

prop_number_equals_unsigned_integer(prop_number_t number, uint64_t val)
    Returns true if the object's value is equivalent to the unsigned value val. If the supplied object isn't a numerical value or if val exceeds INT64_MAX, false is returned.

SEE ALSO
prop_array(3), prop_bool(3), prop_data(3), prop_dictionary(3), prop_object(3), prop_string(3), proplib(3)

HISTORY
The proplib property container object library first appeared in NetBSD 4.0.