**Subject:** trunc/truncf in NetBSD 3

**To:** None *<tech-userlevel@NetBSD.org>*

**From:** Klaus Heinz *<k.heinz@oktsieben.kh-22.de>*

**List:** tech-userlevel

**Date:** 10/06/2007 13:06:17
Hi,
trying to build emulators/qemu I found that it needs a function trunc()
which NetBSD 3 does not provide.
Based on the man page from NetBSD 4
The trunc() and truncf() functions return the nearest integral value with
magnitude less than or equal to |x|. They are equivalent to rint() and
rintf() respectively, in the FP_RZ rounding mode.
I came up with the following workaround:
#include <ieeefp.h>
#include <math.h>
double
trunc( double x) {
fp_rnd rnd_mode = fpsetround(FP_RZ);
double result = rint(x);
rnd_mode = fpsetround(rnd_mode);
return result;
}
On the other hand, there is possible solution in
http://www.NetBSD.org/cgi-bin/query-pr-single.pl?number=36602
which duplicates the trunc() function from -current.
Any opinions?
ciao
Klaus