ReturnReceiptFunction

is an option for MailReceiverFunction that specifies what function to apply if a return receipt is requested for mail received by a MailReceiverFunction.

Details

Typical settings include:
True always allow a return receipt

False never allow a return receipt

fun apply fun to determine whether to give a return receipt
With the setting ReturnReceiptFunction->fun, fun is applied to the same association as in MailReceiverFunction, but with an additional entry "Result" that gives the result from applying the function in MailReceiverFunction.
The function fun is only applied if a return receipt was requested for a particular piece of mail, as indicated by the value for "ReturnReceiptRequested" in the association supplied to MailReceiverFunction.
If the value obtained by applying fun is True, a return receipt is given; otherwise, it is not.

Deploy a mail receiver that only allows return receipts for a certain domain:

Top

	True	always allow a return receipt
	False	never allow a return receipt
	fun	apply fun to determine whether to give a return receipt