O campo é:
debian_revision
This part of the version number specifies the version of the
Debian package based on the upstream version. It may contain
only alphanumerics and the characters + . ~ (plus, full stop,
tilde) and is compared in the same way as the upstream_version
is.
It is optional; if it isn’t present then the upstream_version
may not contain a hyphen. This format represents the case where
a piece of software was written specifically to be turned into a
Debian package, and so there is only one "debianisation" of it
and therefore no revision indication is required.
It is conventional to restart the debian_revision at ’1’ each
time time the upstream_version is increased.
Dpkg will break the version number apart at the last hyphen in
the string (if there is one) to determine the upstream_version
and debian_revision. The absence of a debian_revision compares
earlier than the presence of one (but note that the
debian_revision is the least significant part of the version
number).
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