1 files changed, 18 insertions, 5 deletions

diff --git a/src/lib/libcrypto/man/BIO_push.3 b/src/lib/libcrypto/man/BIO_push.3
index 42afc7659a..5b9e94123f 100644
--- a/src/lib/libcrypto/man/BIO_push.3
+++ b/src/lib/libcrypto/man/BIO_push.3
@@ -1,5 +1,6 @@
-.\"     $OpenBSD: BIO_push.3,v 1.4 2016/11/18 18:52:11 schwarze Exp $
-.\"     OpenSSL 76ed5a42 Jun 29 13:38:55 2014 +0100
+.\"     $OpenBSD: BIO_push.3,v 1.5 2016/12/06 12:54:19 schwarze Exp $
+.\"     OpenSSL doc/man3/BIO_push.pod 76ed5a42 Jun 29 13:38:55 2014 +0100
+.\"     OpenSSL doc/man7/bio.pod a9c85cea Nov 11 09:33:55 2016 +0100
 .\"
 .\" This file was written by Dr. Stephen Henson <steve@openssl.org>.
 .\" Copyright (c) 2000, 2014 The OpenSSL Project.  All rights reserved.
@@ -48,7 +49,7 @@
 .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 .\" OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: November 18 2016 $
+.Dd $Mdocdate: December 6 2016 $
 .Dt BIO_PUSH 3
 .Os
 .Sh NAME
@@ -67,6 +68,13 @@
 .Fa "BIO *b"
 .Fc
 .Sh DESCRIPTION
+BIOs can be joined together to form chains.
+A chain normally consist of one or more filter BIOs
+and one source/sink BIO at the end.
+Data read from or written to the first BIO traverses the chain
+to the end.
+A single BIO can be regarded as a chain with one component.
+.Pp
 The
 .Fn BIO_push
 function appends the BIO
@@ -97,8 +105,9 @@ The process of calling
 .Fn BIO_push
 and
 .Fn BIO_pop
-on a BIO may have additional consequences:
-a control call is made to the affected BIOs.
+on a BIO may have additional consequences: a
+.Xr BIO_ctrl 3
+call is made to the affected BIOs.
 Any effects will be noted in the descriptions of individual BIOs.
 .Sh RETURN VALUES
 .Fn BIO_push
@@ -163,3 +172,7 @@ and the new chain will be
 data can be written to
 .Sy md1
 as before.
+.Sh SEE ALSO
+.Xr BIO_find_type 3 ,
+.Xr BIO_new 3 ,
+.Xr BIO_read 3