NAME

decimal_to_floating, decimal_to_single, decimal_to_double, decimal_to_extended − convert decimal record to floating-point value

SYNOPSIS

/usr/ucb/cc [ flag ... ] file ...

#include <floatingpoint.h>

void decimal_to_single(single ∗px, decimal_mode ∗pm, decimal_record ∗pd,

fp_exception_field_type ∗ps);

void decimal_to_double(double ∗px, decimal_mode ∗pm, decimal_record ∗pd,

fp_exception_field_type ∗ps);

void decimal_to_extended(long double ∗px, decimal_mode ∗pm, decimal_record ∗pd,

fp_exception_field_type ∗ps);

DESCRIPTION

The decimal_to_floating() functions convert the decimal record at ∗pd into a floating-point value at ∗px, observing the modes specified in ∗pm and setting exceptions in ∗ps. If there are no IEEE exceptions, ∗ps will be zero. 

pd→sign and pd→fpclass are always taken into account.  pd→exponent and pd→ds are used when pd→fpclass is fp_normal or fp_subnormal. In these cases pd→ds must contain one or more ASCII digits followed by a NULL.  ∗px is set to a correctly rounded approximation to

(pd→sign)∗(pd→ds)∗10∗∗(pd→exponent)

Thus if pd→exponent == −2 and pd→ds == "1234", ∗px will get 12.34 rounded to storage precision.  pd→ds cannot have more than DECIMAL_STRING_LENGTH −1 significant digits because one character is used to terminate the string with a NULL.  If pd→more!=0 on input then additional nonzero digits follow those in pd→ds; fp_inexact is set accordingly on output in ∗ps.

∗px is correctly rounded according to the IEEE rounding modes in pm→rd. ∗ps is set to contain fp_inexact, fp_underflow, or fp_overflow if any of these arise. 

pd→ndigits, pm→df, and pm→ndigits are not used. 

strtod(3C), scanf(3S), fscanf(), and sscanf() all use decimal_to_double(). 

SEE ALSO

scanf(3S), strtod(3C)

SunOS 5.1  —  Last change: 5 Jul 1990