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Prefix every line with a timestamp

Terminal - Prefix every line with a timestamp
any command | sed "s/^/\[`date +"%Y%m%d%H%M%S"`]/"
2014-02-10 16:18:51
User: brx75x
Functions: command sed
1
Prefix every line with a timestamp

Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives
any command | while read line; do echo "[`date -Iseconds`] $line"; done
2014-02-07 22:27:29
User: ayosec
Functions: command echo read
3

Useful to add a timestamp to every line printed to stdout.

You can use `-Ins` instead of `-Iseconds` if you want more precision.

Know a better way?

If you can do better, submit your command here.

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.

Comment by flatcap 136 weeks and 5 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.

Comment by brx75x 136 weeks and 5 days ago

Your point of view

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