NAME | SYNOPSIS | DESCRIPTION | ATTRIBUTES | SEE ALSO
#include <floatingpoint.h>void decimal_to_single(single *px, decimal_mode *pm, decimal_record *pd, fp_exception_field_type *ps);
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 , pd->ds and pd->ndigits 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 and pd->ndigits is assumed to be the length of the string pd->ds . Notice that for efficiency reasons, the assumption that pd->ndigits == strlen(pd->ds ) is NEVER verified.
On output, *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.
pm->df and pm->ndigits are not used.
strtod(3C) , scanf(3C) , fscanf(3C) , and sscanf(3C) all use decimal_to_double() .
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
---|---|
MT-Level | MT-Safe |
NAME | SYNOPSIS | DESCRIPTION | ATTRIBUTES | SEE ALSO