Sleep until a specific time/date

Question

I want my bash script to sleep until a specific time. So, I want a command like \"sleep\" which takes no interval but an end time and sleeps until then.

The \"at\"-d

Answer 1

On Ubuntu 12.04.4 LTS here is the simple bash input which works :

sleep $(expr `date -d "03/21/2014 12:30" +%s` - `date +%s`)