Section (3) modf
modf, modff, modfl — extract signed integral and fractional values from floating-point number
||long double x,|
|long double *iptr
These functions break the argument
x into an integral part and a
fractional part, each of which has the same sign as
x. The integral part
is stored in the location pointed to by
These functions return the fractional part of
x is a NaN, a
NaN is returned, and *
iptr is set to a NaN.
x is positive
infinity (negative infinity), +0 (−0) is returned, and
iptr is set to
positive infinity (negative infinity).
For an explanation of the terms used in this section, see attributes(7).
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double also conforms to SVr4, 4.3BSD, C89.
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Copyright 1993 David Metcalfe (davidprism.demon.co.uk)
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Linux libc source code
Lewine_zsingle_quotesz_s _POSIX Programmer_zsingle_quotesz_s Guide_ (O_zsingle_quotesz_Reilly & Associates, 1991)
386BSD man pages
Modified 1993-07-24 by Rik Faith (faithcs.unc.edu)
Modified 2002-07-27 by Walter Harms