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Subject: *printf(9) and PRINTF_BUFR_SIZE
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While working on other problems with *printf(9), log(9), etc.
I stumbled upon:

options   PRINTF_BUFR_SIZE=3D128    # Prevent printf output being=20
interspersed.

Question 1: Am I correct in thinking that PRINTF_BUFR_SIZE is supposed
to prevent this:

   ada2: 300.000MB/s transfuhub2: 3 ports with 3 removable, self powered
   ers (SATA 2.x, UDMA6, PIO 8192bytes)
   ada2: Command Queueing enabled

Question 2: Why is vprintf() the only function that does this buffering?
As far as I can tell, the various functions that call kvprintf()=20
directly
without going through vprintf() do not get buffered.  I'm thinking that
kvprintf() would be a better place for the buffering.  Or would this=20
break
something?