Conversion of character string to floating-point number (float type)
float __far atoff(const char __near *nptr);
float __far _COM_atoff_f(const char __far *nptr);
If the partial character string has been converted, the resultant value is returned. If the character string could not be converted, 0 is returned.
If an overflow occurs, atoff returns and sets macro ERANGE to global variable errno.
If an underflow occurs, atoff returns 0 and sets macro ERANGE to global variable errno.
This function converts the first portion of the character string indicated by nptr into a float type representation.