+.\"***************************************************************************
+.\" Copyright (c) 1998-2006,2017 Free Software Foundation, Inc. *
+.\" *
+.\" Permission is hereby granted, free of charge, to any person obtaining a *
+.\" copy of this software and associated documentation files (the *
+.\" "Software"), to deal in the Software without restriction, including *
+.\" without limitation the rights to use, copy, modify, merge, publish, *
+.\" distribute, distribute with modifications, sublicense, and/or sell *
+.\" copies of the Software, and to permit persons to whom the Software is *
+.\" furnished to do so, subject to the following conditions: *
+.\" *
+.\" The above copyright notice and this permission notice shall be included *
+.\" in all copies or substantial portions of the Software. *
+.\" *
+.\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
+.\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
+.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
+.\" IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
+.\" DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
+.\" OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
+.\" THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
+.\" *
+.\" Except as contained in this notice, the name(s) of the above copyright *
+.\" holders shall not be used in advertising or otherwise to promote the *
+.\" sale, use or other dealings in this Software without prior written *
+.\" authorization. *
+.\"***************************************************************************
+.\"
+.\" $Id: gdc.6,v 1.4 2017/09/09 20:04:09 tom Exp $
.TH GDC 6
.SH NAME
gdc \- grand digital clock (curses)
.SH SYNOPSIS
-.B gdc
-[-s] [
-.I n
-]
+.B gdc \fP[\fIoptions\fP] [\fIn\fP]
.SH DESCRIPTION
.I Gdc
-runs a digital clock made of reverse-video blanks on a curses
-compatible VDU screen. With an optional numeric argument
-.I n
+runs a digital clock made of reverse-video blanks on a terminal screen.
+If the terminal supports color, the clock is drawn in red.
+You can make the clock stop, pause or resume by pressing a ``q'',
+``s'' or space, respectively.
+.SH OPTIONS
+.TP
+.B \-d
+use terminal's default colors for the background.
+.TP
+.B \-n
+redirects input to /dev/null, making it ignore the stop/pause commands.
+You can still stop it by pressing the interrupt key.
+.TP
+.B \-s
+makes digits scroll as they change.
+When running on a fast display, the program breaks up the scrolling into
+subsecond repaints, making the operation appear smooth.
+.TP
+.B \-t \fIhh:mm:ss\fP
+specify starting time (default is ``now'').
+.PP
+With an optional numeric argument
+.I num
it stops after
-.I n
-seconds (default never).
-The optional
-.B -s
-flag makes digits scroll as they change. In this curses mode implementation,
-the scrolling option has trouble keeping up.
+.I num
+seconds.
+Normally it runs "forever" (counting down from 2 billion seconds).
.SH AUTHOR
Amos Shapir, modified for curses by John Lupien.
+.br
+Improvements for ncurses by Thomas Dickey.