document log2() and log2f(); from thomas pfaff

ok otto millert martynas

2 files changed, 22 insertions, 5 deletions

diff --git a/lib/libm/Makefile b/lib/libm/Makefile
index cbd7c5a80a8..3b810a5ff39 100644
--- a/lib/libm/Makefile
+++ b/lib/libm/Makefile
@@ -1,4 +1,4 @@
-#  $OpenBSD: Makefile,v 1.70 2009/07/29 18:43:28 martynas Exp $
+#  $OpenBSD: Makefile,v 1.71 2009/10/24 10:06:02 jmc Exp $
 #  $NetBSD: Makefile,v 1.28 1995/11/20 22:06:19 jtc Exp $
 #
 #  @(#)Makefile 5.1beta 93/09/24 
@@ -169,8 +169,8 @@ MAN+=	acos.3 acosh.3 asin.3 asinh.3 atan.3 atan2.3 atanh.3 ceil.3 \
 	copysign.3 ilogb.3 nextafter.3 scalbn.3
 
 MLINKS+=erf.3 erfc.3
-MLINKS+=exp.3 exp2.3 exp.3 expm1.3 exp.3 log.3 exp.3 log10.3 exp.3 log1p.3 \
-	exp.3 pow.3
+MLINKS+=exp.3 exp2.3 exp.3 expm1.3 exp.3 log.3 exp.3 log2.3 \
+	exp.3 log10.3 exp.3 log1p.3 exp.3 pow.3
 MLINKS+=hypot.3 cabs.3
 MLINKS+=scalbn.3 scalbln.3
 MLINKS+=logb.3 scalb.3
@@ -200,6 +200,7 @@ MLINKS+=exp.3 exp2f.3
 MLINKS+=exp.3 expm1f.3
 MLINKS+=exp.3 log10f.3
 MLINKS+=exp.3 log1pf.3
+MLINKS+=exp.3 log2f.3
 MLINKS+=exp.3 logf.3
 MLINKS+=exp.3 powf.3
 MLINKS+=fabs.3 fabsf.3
diff --git a/lib/libm/man/exp.3 b/lib/libm/man/exp.3
index 37ce6a054c3..119d2d4987d 100644
--- a/lib/libm/man/exp.3
+++ b/lib/libm/man/exp.3
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: exp.3,v 1.20 2008/12/12 00:10:26 martynas Exp $
+.\"	$OpenBSD: exp.3,v 1.21 2009/10/24 10:06:02 jmc Exp $
 .\"
 .\" Copyright (c) 1985, 1991 Regents of the University of California.
 .\" All rights reserved.
@@ -29,7 +29,7 @@
 .\"
 .\"     from: @(#)exp.3	6.12 (Berkeley) 7/31/91
 .\"
-.Dd $Mdocdate: December 12 2008 $
+.Dd $Mdocdate: October 24 2009 $
 .Dt EXP 3
 .Os
 .Sh NAME
@@ -42,6 +42,8 @@
 .Nm expm1f ,
 .Nm log ,
 .Nm logf ,
+.Nm log2 ,
+.Nm log2f ,
 .Nm log10 ,
 .Nm log10f ,
 .Nm log1p ,
@@ -70,6 +72,10 @@
 .Ft float
 .Fn logf "float x"
 .Ft double
+.Fn log2 "double x"
+.Ft float
+.Fn log2f "float x"
+.Ft double
 .Fn log10 "double x"
 .Ft float
 .Fn log10f "float x"
@@ -135,6 +141,16 @@ function is a single precision version of
 .Fn log10 .
 .Pp
 The
+.Fn log2
+function computes the value of the logarithm of argument
+.Fa x
+to base 2.
+The
+.Fn log2f
+function is a single precision version of
+.Fn log2 .
+.Pp
+The
 .Fn log1p
 function computes
 the value of log(1+x) accurately even for tiny argument