postfix docs

[Bill Wohler]

David Relson <relson at osagesoftware.com> writes:

> On Thu, 22 Dec 2005 05:54:09 -0500
> Tom Allison wrote:
>
>> I went back to my docs and was reading an example to impliment with postfix.
>> 
>> I'm just curious what this:
>> 
>>   exec <msg.$$ || exit $EX_TEMPFAIL
>> 
>> does.  'exec' ???
>
> Hi Tom,
>
> Honestly, I don't know.  It happens that the postfix docs are descended
> from the qmail docs.  My guess is that there was an editing error and
> the 4 line stanza (beginning with that line) should be deleted (which
> I've done).
>
> Perhaps one of our postfix experts will chip in to say it really
> belongs.

I don't have the context, but I do have a mailman filter script that
has a similar construct. It isn't postfix-specific. Thanks to
someone's well-placed comment, I can explain.

  bogofilter -c $FILTER_CONFIG -e -p > msg.$$ || exit $EX_TEMPFAIL
  if `grep -q 'X-Bogosity: Ham' msg.$$`; then
      exec < msg.$$
      rm -f msg.$$                # safe, we hold the file descriptor
      exec $MAILMAN "$@"
  else
      cat msg.$$ >> spam || exit $EX_TEMPFAIL
      rm -f msg.$$ || exit $EX_TEMPFAIL
      exit $EX_NOPERM
  fi

The first line, with the bogofilter command, is using the original
message from stdin. It creates a new message in msg.$$ that has the
bogofilter header field. The "exec < msg.$$" line puts that new
message on stdin so that we can delete the temporary file while still
passing it on mailman's stdin.

-- 
Bill Wohler <wohler at newt.com>  http://www.newt.com/wohler/  GnuPG ID:610BD9AD
Maintainer of comp.mail.mh FAQ and MH-E. Vote Libertarian!
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