#!/bin/bash
## constructs a List-Difference, those on first list but not on 2nd list, for lists of email-addresses;  by Eugene Reimer  2007-Nov01;
##	eg: to send to ELIST-Regina - but only to those NOT receiving the Elist-emailings.
##
## Input Lines can be:
##	NameComment <email-id>					<--uniquify-emailidlist script caters to this format, even to combining NameComments...
##	NameComment <email-id>(TAB)##comment
##	email-id(TAB)##comment					<--harvest-emailids script produces this format (comment shows the source webpage)
## The Output will be without (TAB)##comment, as wanted by sendtoElist script.
##
## USAGE EXAMPLE:
##	ListSubtract-e  ELIST-Regina  Elist-20071027  >ELIST-Regina-lessElist

[ $# -ne 2 ] && { echo "usage:  ListSubtract-e  ELIST-XX  Elist-YY  >ELIST-XX-less-YY";  exit; }

while read; do							##read line by line...
  TRIM=${REPLY%%	*}					##remove TAB+comment if present
  ID=${TRIM#*<};  ID=${ID%>*}					##remove NameComment if present
  if ! grep -q $ID $2;then echo "$TRIM"             >&1		##output line to stdout,  using $ID for matching, but producing $TRIM
  ##else                   echo "--removing $REPLY" >&2		##removing msg to stderr (DEBUG only)
  fi
done  <$1							##reads from first param


exit
Notes for myself:
	ELIST-Regina     has:  NameComment <email-id>
	ELIST-OrchidMall has:  email-id(TAB)##comment