-x on Postfix, and a possible fix.

[Tony Shadwick]

Okay, so quick search yields that no one else has fought with this yet, 
and since I'm the on that asked for the feature way back when, I guess 
it is only appropriate that I'm asking for this too. :)

In short - `sendmail -bv` does not behave as expected on Postfix.  I've 
known this for about a year, but him-hawed about speaking up.  Now it's 
biting me in the rear.  Instead of printing to the terminal the results, 
it emails the current user the results.

I did quite a bit of research on the matter, and it has something to do 
with postfix not being run as root or somesuch.  Whatever the reason, 
there's really no way to make `sendmail -bv` behave as it does with 
sendmail.

The alternative would be to provide what I call spamass-milter -y, which 
would be to bring your own expansion command.  Convienently for me, I 
have one handy:

tshadwick# postmap -q address@hidden /etc/postfix/virtual
tshadwick

One could, in fact ditch -x and use -y on the same system by doing this:

tshadwick# sendmail -bv address@hidden | grep "deliverable: 
mailer local" | awk '/mailer local, user (.*?)/ {print $6}'
numbski

(different machines - output from both is accurate).

So I guess what I proprose is allow -y to call a single command (I could 
do the above example in a script), and it would then behave as -x does 
today.

The reason I believe this is important is because I have another site 
running postfix where postmap -q wouldn't do the job.  They are using 
postfix's mysql capability.  I could however structure a script to query 
mysql and return the correct result.  It would allow proper 
customization all the way around.

For now, I guess I can recompile spamass-milter and just change the 
behavior of -x, but long-term I expect more users to go from sendmail to 
postfix, and the result of -x right now on postfix isn't good - it 
leaves a ton of zombie processes waiting to get an answer back.  Not 
your fault - you wrote this for sendmail, not postfix.  Personally, I 
feel like the Postfix project is being somewhat obstinate about the 
whole thing - lots of people rely on sendmail -bv's behavior.  Simply 
allowing us to throw a flag or set a variable to get the old behavior 
back would be trivial, but they have repeatedly refused to do so.  This 
fixes that.

Tony Shadwick