Simple way to convert HH:MM:SS (hours:minutes:seconds.split seconds) to seconds

Question

What\'s an easy way to convert 00:20:40.28 (HH:MM:SS) to seconds with a Bash script?

Split seconds can be cut out, it’s not essential.

Answer 1

If you don't know what exactly do you have - SS, MM:SS or HH:MM:SS, like after youtube-dl --get-duration, then awk magic could be useful:

echo 12 | awk -F\: '{ for(k=NF;k>0;k--) sum+=($k*(60^(NF-k))); print sum }'
12
echo 35:12 | awk -F\: '{ for(k=NF;k>0;k--) sum+=($k*(60^(NF-k))); print sum }'
2112
echo 1:35:12 | awk -F\: '{ for(k=NF;k>0;k--) sum+=($k*(60^(NF-k))); print sum }'
5712