fastforward - 1:0.51-10 main

It can create forwarding databases from a sendmail-style /etc/aliases or
from user-oriented virtual-domain tables.
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fastforward supports external mailing lists, stored in a binary format for
fast access. It has a tool to convert sendmail-style include files into
binary lists.
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fastforward is more reliable than sendmail. sendmail can't deal with long
aliases, or deeply nested aliases, or deeply nested include files;
fastforward has no limits other than memory. sendmail can produce corrupted
alias files if the system crashes; fastforward is crashproof.
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fastforward's database-building tools are much faster than sendmail's
newaliases. Even better, fastforward deliveries don't pause while the
database is being rebuilt.
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fastforward does not support insecure sendmail-style program deliveries from
include files; you can use qmail's secure built-in mechanisms instead.
fastforward does support program deliveries from /etc/aliases.