UNIX for Dummies Questions & Answers

Hello all
This is a sample vmstat output ...

$ vmstat 2 2

kthr memory page disk faults cpu
r b w swap free re mf pi po fr de sr hx hx hx hx in sy cs us sy id
1 0 0 23105784 7810488 323 767 1742 5 5 0 0 0 0 0 0 683 780 457 43
0 0 0 25216784 8648872 0 2 0 3 3 0 0 0 0 0 0 825 333 671 1 12

I would like to append the date & timestamp, to the end of each line, of the vmstat output, so that the output looks like something like below ...


kthr memory cpu
r b w swap free re .... cs us sy id
1 0 0 23105784 7810488 ....3 457 43 24 33 11/14/2006 15:30:35
0 0 0 25216784 8648872 ....0 671 1 12 87 11/14/2006 15:30:38
0 0 0 25216784 8648880 ....4 755 1 15 84 11/14/2006 15:30:41
0 0 0 25216784 8648888 ....01550 3 15 82 11/14/2006 15:30:44
0 0 0 25216784 8648888 ....0 763 1 11 88 11/14/2006 15:30:47

I tried something like this, but it did not work ...Any ideas ...

$ vmstat 3 5 | date '+%m-%d-%Y %H:%M:%S'

Thanks

You could use a function. You don't say which shell you are using, but this should work for ksh and bash...

Code:

function eg {
  while read line
  do
    printf "$line"
    date '+ %m-%d-%Y %H:%M:%S'
  done
}

..then you can pipe your command through the function, like this...

Code:

vmstat 3 5 | eg

Awesome ! ...works like a charm ...Thanks a lot Ygor ...

unfortunately ALL the timestamps will be the same as ALL your input into the pipe come in one big chunk.

ooops, nevermind.
hmmm..... I wonder why does it as what it does. Pipes into functions are NOT buffered?.....

if I do:

Code:

vmstat 3 5 | sed "s/$/$(date)/"

all the timestamps are the same.....

With:
vmstat 3 5 | sed "s/$/$(date)/"
the shell evaluates $(date) before the pipeline starts to run. Only one invocation of date is why the timestamp won't change. Ygor's solution reruns the date command for each line of output.

ok - good explanation - thanks