Dallman Ross wrote,
| If someone writes to both her and me, they receive two acknowledgments
| from her and none from me. If I tell "her" recipe not to invoke if I,
| too, am on the To: line, then they get two from me, and none from her.
OK, it seems you're depending on the visible headers to determine which
messages are for you and which are for her. You really need to know who
was the envelope recipient of each piece.
How is her .forward set up? Just with your address? Ouch, double ouch.
I hope not. Do forwards of her mail come to you with an extra Received:
header by which they can be distinguished from mail sent directly to you?
If her .forward invokes a setuid root procmail binary -d you, you can add
the -a something option to the procmail command line in your .forward,
and then your rcfiles can tell who the envelope recipient is:
ARG=$1
:0
* ARG ?? something
{ RECIPIENT=me }
:0E
* ARG ?? ^^^^
{ RECIPIENT=her }
:0E
{ RECIPIENT=interloper }
and thereafter procmail can distinguish mail for her from mail for you
without relying on the visible headers, which can't tell the two copies apart
when something is sent to both of you (or worse, when it is blind carboned
to both of you).