countdown.sh

#!/bin/bash

# countdown timer, for use with OBS Studio or the like
# writes a mm:ss countdown to a file every second

# Usage: ./countdown.sh SECS FILENAME

### CAUTION: there is no error checking at all
### and FILENAME WILL GET CLOBBERED!

# if you are using MacOS, you will need to install gdate
#   using homebrew: brew install coreutils
# if on Windows, you'll want to install Ubuntu on Windows
#   using: https://ubuntu.com/tutorials/ubuntu-on-windows

for i in $(seq $1 0) ; do
#    if [ "$i" -gt 59 ] ; then 
        gdate -d@$i -u +%M:%S > $2
#    else
#        gdate -d@$i -u +%S
#    fi
    sleep 1
done