Lars Ellenberg <[EMAIL PROTECTED]> wrote:
> it may be that the "original" version was done this way to increase the
> likelihood for the whole message to get to the fifo as _one_ blob,
> relying on the internal buffering of the first of the 'cat's.
> 
> doing "echo >> $HA_FIFO; cat >> $FIFO; echo >> $HA_FIFO", the fifo
> would be open/write/fflush/close by bash/sh/the commands three times.
> 
> doing (echo ; cat ; echo ) >> $FIFO, bash/sh should only open/close it
> once, but each of the commands would imply a dup/write/fflush/close,
> all making it more likely that concurrent users of that function would
> garble each others messages.
> 
> but thats just me guessing after doing shell magic since quite a while
> with lots of different versions of different shells...

Concurrency is probably very nasty here regardless.
But I agree that either

(echo ">>>"; cat -; echo "<<<") >> $HA_FIFO

or  your version with cat - at the end is a bit nicer with respect to
this. than the 3 x >> approach. Though personally I think the extra cat
- is clutching at straws.

-- 
Horms
  H: http://www.vergenet.net/~horms/
  W: http://www.valinux.co.jp/en/


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