[Inadvertently deleted the thread, so sorry for an orhpaned reply.]

I think the problem is that less(1) trusts the file size returned by
stat(2) and, as Simon noted in his reply, it seems that stat(2)
returns the amount of free space in the msgbug, not the amount of
space used.

On my sparc:

    $ cat /kern/msgbuf | wc -c
       8176
    $ ls -l /kern/msgbuf
    -r--r--r--  1 root  wheel  5736 Oct 10 23:22 /kern/msgbuf
    $ dmesg | wc -c
        2434
    $ expr 2434 + 5736
        8170		# <- ok, ok, it doesn't add up to 8176 ;)

After forcing some kernel output I get

      dmesg: 2540
      stat:  5630
      sum:   8170

And so on.

SY, Uwe
-- 
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