1.Dd January 15, 2023 2.Dt GRDC 6 3.Os 4.Sh NAME 5.Nm grdc 6.Nd grand digital clock (curses) 7.Sh SYNOPSIS 8.Nm 9.Op Fl st 10.Op Ar n 11.Nm 12.Fl c 13.Ar n 14.Sh DESCRIPTION 15.Nm 16runs a digital clock made of reverse-video blanks on a curses 17compatible VDU screen. 18With an optional numeric argument 19.Ar n 20it stops after 21.Ar n 22seconds (default never). 23The clock can act as a countdown timer with the 24.Fl c 25flag, 26.Ar n 27specifies the number of seconds to time for. 28The optional 29.Fl s 30flag makes digits scroll as they change. 31The optional 32.Fl t 33flag tells grdc to output the time in a 12-hour format. 34In this curses mode implementation, 35the scrolling option has trouble keeping up. 36.Sh ENVIRONMENT 37.Bl -tag -width Ds 38.It Ev TZ 39The time zone to use for displaying the time. 40It is normally specified as a pathname relative to 41.Pa /usr/share/zoneinfo , 42though see 43.Xr tzset 3 44for more information. 45If this variable is not set, the time zone is determined based on 46.Pa /etc/localtime . 47.El 48.Sh NOTES 49In countdown timer mode, the specifying of 50.Fl n 51> 360000 seconds (100 hours) will lead to the counter displaying 52incorrect remaining time, however it will time correctly, and 53display correctly when the remaining time becomes less than 54100 hours. 55.Sh AUTHORS 56.An -nosplit 57.An Amos Shapir , 58modified for curses by 59.An John Lupien . 60Countdown timer mode by 61.An Gavin Atkinson . 62