F=m
Allow delivery to multiple recipients All versions
Whenever the sendmail program
executes the program specified by the P=
delivery agent equate
(P= on page 748), that
program is given its argv
vector as specified by the
A=
delivery
agent equate (A= on page
738). As the last step in building that argv
,
sendmail appends one or more
recipient addresses.
The decision as to whether it appends one address or
many is determined by the F=m
delivery agent flag. If this flag
is absent, the delivery agent is given only one
recipient. Otherwise, if it is present, the delivery
agent can be given many recipients (subject to any
limitation imposed by the MaxRecipientsPerMessage
option, MaxRecipientsPerMessage on page 1050).
In either case, if there are more recipients than
argv
can
accept, the delivery agent is rerun as many times as
is necessary to handle them all.
Note that sendmail is able to distinguish only between failures involving one, many, or all of the recipients when it is delivering with SMTP or LMTP. Otherwise, it judges delivery as successful if a zero exit(2) value is returned by a delivery agent. If the delivery agent fails to deliver to one of many recipients, it exits with a nonzero value, and because of that single failure, sendmail will presume that delivery to all recipients failed. If the error is temporary, this can result in duplicate delivery to each recipient listed prior to the bad recipient.
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