Prefix every line with a timestamp

any command | sed "s/^/\[`date +"%Y%m%d%H%M%S"`]/"

By: brx75x
2014-02-10 16:18:51

1 Alternatives + Submit Alt

  • Useful to add a timestamp to every line printed to stdout. You can use `-Ins` instead of `-Iseconds` if you want more precision. Show Sample Output

    any command | while read line; do echo "[`date -Iseconds`] $line"; done
    ayosec · 2014-02-07 22:27:29 0

What Others Think

That's what I immediately thought when I saw the other command. But ayosec's is better and the difference is subtle. The difference will show up for any command that takes more than one second. Your command will prefix ALL the output with a SINGLE date. ayosec's command creates a NEW date stamp for each line WHEN IT OCCURS.
flatcap · 368 weeks and 2 days ago
Good point. In fact I use mine not with 'any command' but mostly with `tail -f file | ` or `while [ 1 ]; do something; done | ` stuff.
brx75x · 368 weeks and 1 day ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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