I went nuts and wrote a generic rint implementation. I think it is

correct per the man page and a little testing seems to show it works.
 -Erik

TODO

@@ -13,7 +13,6 @@ run 'nm -D --size-sort -t d libuClibc-0.9.5.so' and work on the biggest things
     (i.e. stuff at the end of the list) to make them smaller.
 make inb/outb work (for lilo et all)
 	update: done for i386.  lilo and the pcmcia tools compile cleanly now
-make rint work (for ip et all)
 include/resolv.h does not define struct _res, and libc/inet/resolv.c
     does not use this struct.  res_init does nothing.  the other res_* 
     functions are not implemented.

libm/double/Makefile

@@ -35,7 +35,7 @@ CSRC=acosh.c airy.c asin.c asinh.c atan.c atanh.c bdtr.c beta.c \
 	polevl.c polmisc.c polylog.c polyn.c pow.c powi.c psi.c rgamma.c round.c \
 	shichi.c sici.c sin.c sindg.c sinh.c spence.c stdtr.c struve.c \
 	tan.c tandg.c tanh.c unity.c yn.c zeta.c zetac.c \
-	sqrt.c floor.c setprec.c mtherr.c noncephes.c
+	sqrt.c floor.c setprec.c mtherr.c noncephes.c rint.c
 
 COBJS=$(patsubst %.c,%.o, $(CSRC))
 

libm/double/rint.c

@@ -0,0 +1,52 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * rint for uClibc
+ *
+ * Copyright (C) 2001 by Lineo, inc.  
+ * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Library General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include <math.h>
+
+/* From the Linux man page:
+ *
+ * NAME
+ *	rint - round to closest integer
+ *
+ * SYNOPSIS
+ *	#include <math.h>
+ *	double rint(double x);
+ *
+ * DESCRIPTION
+ *	The rint() function rounds x to an integer value according
+ *	to the prevalent rounding mode.  The default rounding mode
+ *	is to round to the nearest integer.  
+ *
+ * RETURN VALUE
+ *	The rint() function returns the integer value as a float­ 
+ *	ing-point number.
+ */
+
+double rint (double x) {
+	double low = floor(x);
+	if (fmod(x,low) >= (double)0.5)
+		return(ceil(x));
+	else
+		return(low);
+}
+