Sometimes it’s really useful to prepend a timestamp to every output line of a command. This can be done fairly easily:
$command | \ perl -pe '@now=localtime();printf "%04d-%02d-%02dT%02d:%02d:%02d ",$now[5]+1900,$now[4]+1,$now[3],$now[2],$now[1],$now[0];'
The perl command reads in every line, prints the current time in the default format (or in whatever format you specify), followed by the read line.
