The quotes around the vacation program are necessary to prevent the program and
its single argument (user) from being viewed as two separate addresses. The vacation
program is run withth e command-line argument user, and the mail message is
given to it via its standard input.
Beginning withV8 sendmail, a user must have a valid shell to run programs from the
~/.forward file and to write files via the ~/.forward file. See ?§4.8.3 on page 180 for a
description of this process and for methods to circumvent it at the system level.
Because sendmail sorts all addresses and deletes duplicates before delivering to any of
them, it is important that programs in ~/.forward files be unique. Consider a program
that doesn??™t take an argument and suppose that two users both specified that
program in their ~/.forward files:
user 1 ?†’ \user1, "|/bin/notify"
user 2 ?†’ \user2, "|/bin/notify"
Prior to V8 sendmail, when mail was sent to both user1 and user2, the address /bin/
notify appeared twice in the list of addresses. The sendmail program eliminated what
seems to be a duplicate,* and one of the two users did not have the program run.
* V8 sendmail uses the owner of the ~/.forward file in addition to the program name when comparing.
This is the Title of the Book, eMatter Edition
Copyright ?© 2007 O??™Reilly & Associates, Inc. All rights reserved.
Pages:
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904