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

This would work even if you don't specify hours or minutes: echo "04:20:40" | sed -E 's/(.*):(.+):(.+)/\1*3600+\2*60+\3/;s/(.+):(.+)/\1*60+\2/' | bc