freebsd-skq/lib/libc/gen/modf.3
David Schultz 838200ff96 Document modff() and modfl(). Technically, modff() and modfl()
live in libm, while modf() lives in libc due to historical
mistakes. I'm claiming in the manpage that they all live in libm,
since programmers should not rely on the mistake.
2008-03-29 16:19:35 +00:00

82 lines
2.6 KiB
Groff

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.\" @(#)modf.3 8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
.\"
.Dd March 29, 2008
.Dt MODF 3
.Os
.Sh NAME
.Nm modf ,
.Nm modff ,
.Nm modfl
.Nd extract signed integral and fractional values from floating-point number
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn modf "double value" "double *iptr"
.Ft float
.Fn modff "float value" "float *iptr"
.Ft long double
.Fn modfl "long double value" "long double *iptr"
.Sh DESCRIPTION
The
.Fn modf ,
.Fn modff ,
and
.Fn modfl
functions break the argument
.Fa value
into integral and fractional parts, each of which has the
same sign as the argument.
It stores the integral part as a
floating point number
in the object pointed to by
.Fa iptr .
.Sh RETURN VALUES
These functions return the signed fractional part of
.Fa value .
.Sh SEE ALSO
.Xr frexp 3 ,
.Xr ldexp 3 ,
.Xr math 3
.Sh STANDARDS
The
.Fn modf ,
.Fn modff ,
and
.Fn modfl
functions conform to
.St -isoC-99 .