1 files changed, 14 insertions, 2 deletions

diff --git a/src/lib/libc/string/bzero.3 b/src/lib/libc/string/bzero.3
index 1fd5da81b5..8476eb863e 100644
--- a/src/lib/libc/string/bzero.3
+++ b/src/lib/libc/string/bzero.3
@@ -27,9 +27,9 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     $OpenBSD: bzero.3,v 1.9 2013/06/05 03:39:23 tedu Exp $
+.\"     $OpenBSD: bzero.3,v 1.10 2014/01/22 21:06:45 tedu Exp $
 .\"
-.Dd $Mdocdate: June 5 2013 $
+.Dd $Mdocdate: January 22 2014 $
 .Dt BZERO 3
 .Os
 .Sh NAME
@@ -39,6 +39,8 @@
 .In string.h
 .Ft void
 .Fn bzero "void *b" "size_t len"
+.Ft void
+.Fn explicit_bzero "void *b" "size_t len"
 .Sh DESCRIPTION
 The
 .Fn bzero
@@ -51,6 +53,12 @@ If
 is zero,
 .Fn bzero
 does nothing.
+.Pp
+The
+.Fn explicit_bzero
+variant behaves the same, but will not be removed by a compiler's dead store
+optimization pass, making it useful for clearing sensitive memory such as a
+password.
 .Sh SEE ALSO
 .Xr memset 3 ,
 .Xr swab 3
@@ -59,3 +67,7 @@ The
 .Fn bzero
 function first appeared in
 .Bx 4.2 .
+The
+.Fn explicit_bzero
+function first appeared in
+.Ox 5.5 .