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Date: Fri, 28 Nov 2003 16:01:33 -0800
From: Steve Kargl <sgk@troutmask.apl.washington.edu>
To: freebsd-standards@freebsd.org
Message-ID: <20031129000133.GA30662@troutmask.apl.washington.edu>
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Subject: Implementing C99's roundf(), round(), and roundl()
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Can the math functions round[fl]() be implemented in
terms of other math(3) functions and still conform to the 
C99 and POSIX standard?  For example,

#include <math.h>

float roundf(float x) {
	float t;
	if (x >= 0.0) {
		t = ceilf(x);
		if ((t - x) > 0.5) t -= 1.0;
		return t;
	} else {
		t = ceilf(-x);
		if ((t + x) > 0.5) t -= 1.0;
		return -t;
	}
}


-- 
Steve