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Countdown Clock

Terminal - Countdown Clock
MIN=10;for ((i=MIN*60;i>=0;i--));do echo -ne "\r$(date -d"0+$i sec" +%H:%M:%S)";sleep 1;done
2011-02-20 11:56:28
User: flatcap
Functions: echo sleep
11
Countdown Clock

Countdown clock - Counts down from $MIN minutes to zero.

I let the date command do the maths.

This version doesn't use seq.

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
MIN=1 && for i in $(seq $(($MIN*60)) -1 1); do echo -n "$i, "; sleep 1; done; echo -e "\n\nBOOOM! Time to start."
2010-06-20 15:19:12
User: atoponce
Functions: echo seq sleep
Tags: timer counter
10

Simple countdown clock that should be quite portable across any Bourne-compatible shell. I used to teach for a living, and I would run this code when it was time for a break. Usually, I would set "MIN" to 15 for a 15-minute break. The computer would be connected to a projector, so this would be projected on screen, front and center, for all to see.

function countdown { case "$1" in -s) shift;; *) set $(($1 * 60));; esac; local S=" "; for i in $(seq "$1" -1 1); do echo -ne "$S\r $i\r"; sleep 1; done; echo -e "$S\rBOOM!"; }
2010-06-30 12:20:01
User: kniht
Functions: echo seq set sleep
Tags: timer counter
1

The biggest advantage over atoponce's nifty original is not killing the scrollback. Written assuming bash, but shouldn't be terribly difficult to port to other shells. S should be multiple spaces, but I can't get commandlinefu to save/show them properly, any help?

MIN=10 && for i in $(seq $(($MIN*60)) -1 1); do printf "\r%02d:%02d:%02d" $((i/3600)) $(( (i/60)%60)) $((i%60)); sleep 1; done

Know a better way?

If you can do better, submit your command here.

What others think

wonderful, I made a function out of it to be more variable:

countdown () { MIN=$1; for ((i=$((MIN*60));i>=0;i--));do echo -ne "\r$(date -d"0+$i sec" +%H:%M:%S)";sleep 1;done;}

to call it with "countdown 10" for 10 min, "countdown 5" for 5 min, ...

thx

Comment by tcfusion 200 weeks and 1 day ago

You're already in an arithmetic context in the for statement. There's no need for $(()):

MIN=10;for ((i=MIN*60;i>=0;i--));do echo -ne "\r$(date -d"0+$i sec" +%H:%M:%S)";sleep 1;done
Comment by dennisw 199 weeks ago

@dennisw: Very good point. Thanks for that. I've updated the command.

Comment by flatcap 199 weeks ago

test this!

MIN=1;for ((i=MIN*60;i>=0;i--));do echo -ne "\r$(date -d"0+$i sec" +%H:%M:%S)";sleep 1;ls ; done

Comment by el3ctron 196 weeks and 5 days ago

Hi,

How do I get this to work on Ksh88 :-(-

Comment by newbie01linux 118 weeks and 5 days ago

hi flatcap

do you know how I can get your command to work in ksh88?

Comment by newbie01linux 118 weeks and 5 days ago

@newbie01linux: Sorry, I don't know and I don't have access to ksh88.

Fedora has ksh93 and the command works in that.

Comment by flatcap 118 weeks and 4 days ago

Your point of view

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