математические декларации (mathematical declarations)
Обоснование (Rationale)
Before the ISO/IEC 9899:1999 standard, the math library was
defined only for the floating type double. All the names formed
by appending 'f' or 'l' to a name in <math.h> were reserved to
allow for the definition of float and long double libraries; and
the ISO/IEC 9899:1999 standard provides for all three versions of
math functions.
The functions ecvt(), fcvt(), and gcvt() have been dropped from
the ISO C standard since their capability is available through
sprintf().
