To arrange for requeuing of the message on failure, users should be
encouraged to construct their ~/.forward files like this:
"| /usr/local/lib/slocal -user george || exit 75"
Here, the || tells the Bourne shell to perform what follows (the exit 75) if the preceding
program could not be executed or if the program exited because of an error.
The exit value 75 is special, in that it tells sendmail to queue the message for later
delivery rather than to bounce it.
13.9 Pitfalls
??? When sendmail collects addresses, it discards duplicates. Prior to V8 sendmail,
program entries in a ~/.forward file had to be unique; otherwise, an identical
entry in another user??™s ~/.forward caused one or the other to be ignored. Usually,
this is solved by requiring the program to take an argument. If the program
won??™t accept an argument, add a shell comment inside the quotes.
??? The database forms of the aliases(5) file contain binary integers. As a consequence,
those database files cannot be shared via network-mounted filesystems
by machines of differing architectures. This has been fixed with V8 sendmail,
which can use the Sleepycat db(3) form of database??”if you define NEWDB
(?§3.4.34 on page 128) when building sendmail.
??? As network-mounted filesystems become increasingly common, the likelihood that
a user??™s home directory will be temporarily unavailable increases.
Pages:
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907