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ROUND(P)			    POSIX Programmer's Manual				 ROUND(P)

       round, roundf, roundl - round to the nearest integer value in a floating-point format

       #include <math.h>

       double round(double x);
       float roundf(float x);
       long double roundl(long double x);

       These  functions shall round their argument to the nearest integer value in floating-point
       format, rounding halfway cases away from zero, regardless of the current  rounding  direc-

       An  application	wishing  to  check for error situations should set errno to zero and call
       feclearexcept(FE_ALL_EXCEPT) before calling these functions.  On return, if errno is  non-
       zero  or fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero,
       an error has occurred.

       Upon successful completion, these functions shall return the rounded integer value.

       If x is NaN, a NaN shall be returned.

       If x is +-0 or +-Inf, x shall be returned.

       If the correct value would  cause  overflow,  a	range  error  shall  occur  and  round(),
       roundf(),  and  roundl()  shall return the value of the macro +-HUGE_VAL, +-HUGE_VALF, and
       +-HUGE_VALL (with the same sign as x), respectively.

       These functions may fail if:

       Range Error
	      The result overflows.

       If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, then errno shall be
       set  to	[ERANGE].  If  the integer expression (math_errhandling & MATH_ERREXCEPT) is non-
       zero, then the overflow floating-point exception shall be raised.

       The following sections are informative.


       On  error,  the	expressions  (math_errhandling	&  MATH_ERRNO)	and  (math_errhandling	&
       MATH_ERREXCEPT) are independent of each other, but at least one of them must be non-zero.



       feclearexcept()	,  fetestexcept()  , the Base Definitions volume of IEEE Std 1003.1-2001,
       Section 4.18, Treatment of Error Conditions for Mathematical Functions, <math.h>

       Portions of this text are reprinted and	reproduced  in	electronic  form  from	IEEE  Std
       1003.1,	2003  Edition,	Standard  for Information Technology -- Portable Operating System
       Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003  by
       the  Institute  of  Electrical  and  Electronics Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE  and  The  Open  Group
       Standard, the original IEEE and The Open Group Standard is the referee document. The orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group			       2003					 ROUND(P)
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