Note: the 'env' program listed below is not part of the standard NeXTStep filesystem, but can
be found here:

ftp://next-ftp.peak.org/pub/next/apps/utils/unix/GNU_sh-utils.1.16.NIHS.b.tar.gz


rblcheck-1.2:

from docs/README:

	This program is a very basic interface to Paul Vixie's RBL
	filter.  The basic idea of the filter is that when someone
	is blacklisted for an email abuse, a new domain name is
	resolved in the form of "a.b.c.d.rbl.maps.vix.com", where
	"a.b.c.d" is actually the IP address "d.c.b.a". For example,
	if the IP address 127.0.0.2 were listed as a blacklisted
	address, "2.0.0.127.rbl.maps.vix.com" would have a DNS
	entry (this is a real example; that address is in place as
	a verification mechanism).

######################################################################

Changes:

in src/utils/dns/dump.c I had to change

	#include <getopt.h>

to

	#include </NextDeveloper/Source/GNU/cc/cc/getopt.h>

Original source code found at: http://www.xnet.com/~emarshal/rblcheck/   

######################################################################

To use with SENDMAIL and PROCMAIL:

This is what I had:

Mlocal,		P=/usr/local/bin/procmail, F=lsDFMAw5:/|@qSPfhn9, S=10/30, R=20/40,
		T=DNS/RFC822/X-Unix,
		A=procmail -Y -a $h -d $u
Mprog,		P=/bin/sh, F=lsDFMoqeuP, S=10/30, R=20/40, D=$z:/,
		T=X-Unix,
		A=sh -c $u


This is what I changed it to:

Mlocal,		P=/usr/local/gnu/bin/env, F=lsDFMAw5:/|@qSPfhn9, S=10/30, R=20/40,
		T=DNS/RFC822/X-Unix,
		A=env TCPREMOTEIP="${client_addr}" sh -c $u
Mprog,		P=/usr/local/gnu/bin/env, F=lsDFMoqeuP, S=10/30, R=20/40, D=$z:/,
		T=X-Unix,
		A=env TCPREMOTEIP="${client_addr}" sh -c $u

and use procmail with a $HOME/.forward file (all one line):

"|IFS=' '&&p=/usr/local/bin/procmail&&test -x $n&&exec $p -Ypf-||exit 75 #luomat"

(Note the 'p' in the 'Ypf' which 'man procmail' tells us means:

     -p   Preserve any old environment.  Normally procmail clears
	  the  environment  upon startup, except for the value of
	  TZ.  However, in any	case:  any  default  values  will
	  override  any  preexisting  environment variables, i.e.
	  procmail will not pay any attention to  any  predefined
	  environment  variables,  it will happily overwrite them
	  with its own defaults.  For  the  list  of  environment
	  variables  that  procmail  will  preset  see	the proc-
	  mailrc(5) man page.  If both -p and -m  are  specified,
	  the  list  of  preset  environment variables shrinks to
	  just: LOGNAME, HOME, SHELL, ORGMAIL and MAILDIR.

which is how we can use the variable ``TCPREMOTEIP'' in our
.procmailrc (see the docs/INSTALL document for procmail recipes
for using RBL)

My thanks to the author "Edward S. Marshall" <emarshal@logic.net>
for making code changes to make this compile out of the box for
NeXTStep.

See the documents in docs/ for important license information (GPL)
and other important information.