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FMOD(3)                    Linux Programmer's Manual                   FMOD(3)

NAME
       fmod, fmodf, fmodl - floating-point remainder function
SYNOPSIS
       #include <math.h>
       double fmod(double x, double y);
       float fmodf(float x, float y);
       long double fmodl(long double x, long double y);
       Link with -lm.
   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
       fmodf(), fmodl():
           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
           or cc -std=c99
DESCRIPTION
       The fmod() function computes the floating-point remainder of dividing x
       by y.  The return value is x - n * y, where n is the quotient of x / y,
       rounded toward zero to an integer.
RETURN VALUE
       On success, these functions return the value x - n*y, for some  integer
       n,  such that the returned value has the same sign as x and a magnitude
       less than the magnitude of y.
       If x or y is a NaN, a NaN is returned.
       If x is an infinity, a domain error occurs, and a NaN is returned.
       If y is zero, a domain error occurs, and a NaN is returned.
       If x is +0 (-0), and y is not zero, +0 (-0) is returned.
ERRORS
       See math_error(7) for information on how to determine whether an  error
       has occurred when calling these functions.
       The following errors can occur:
       Domain error: x is an infinity
              errno  is set to EDOM (but see BUGS).  An invalid floating-point
              exception (FE_INVALID) is raised.
       Domain error: y is zero
              errno is set  to  EDOM.   An  invalid  floating-point  exception
              (FE_INVALID) is raised.
CONFORMING TO
       C99, POSIX.1-2001.  The variant returning double also conforms to SVr4,
       4.3BSD, C89.
BUGS
       Before version 2.10, the glibc implementation did not set errno to EDOM
       when a domain error occurred for an infinite x.
SEE ALSO
       remainder(3)
COLOPHON
       This  page  is  part of release 3.53 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

                                  2012-03-15                           FMOD(3)