===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/tmux/tmux.1,v
retrieving revision 1.854
retrieving revision 1.855
diff -u -r1.854 -r1.855
--- src/usr.bin/tmux/tmux.1	2021/08/13 18:54:54	1.854
+++ src/usr.bin/tmux/tmux.1	2021/08/27 17:15:57	1.855
@@ -1,4 +1,4 @@
-.\" $OpenBSD: tmux.1,v 1.854 2021/08/13 18:54:54 nicm Exp $
+.\" $OpenBSD: tmux.1,v 1.855 2021/08/27 17:15:57 nicm Exp $
 .\"
 .\" Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
 .\"
@@ -14,7 +14,7 @@
 .\" IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 .\" OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: August 13 2021 $
+.Dd $Mdocdate: August 27 2021 $
 .Dt TMUX 1
 .Os
 .Sh NAME
@@ -1331,7 +1331,7 @@
 .Op Fl cDlLRSU
 .Op Fl A Ar pane:state
 .Op Fl B Ar name:what:format
-.Op Fl C Ar XxY
+.Op Fl C Ar size
 .Op Fl f Ar flags
 .Op Fl t Ar target-client
 .Op Ar adjustment
@@ -1375,7 +1375,17 @@
 it.
 .Pp
 .Fl C
-sets the width and height of a control mode client.
+sets the width and height of a control mode client or of a window for a
+control mode client,
+.Ar size
+must be one of
+.Ql widthxheight
+or
+.Ql window ID:widthxheight ,
+for example
+.Ql 80x24
+or
+.Ql @0:80x24 .
 .Fl A
 allows a control mode client to trigger actions on a pane.
 The argument is a pane ID (with leading