формат номера версии пакета Debian (Debian package version number format)
Имя (Name)
deb-version - Debian package version number format
Синопсис (Synopsis)
[epoch:]upstream-version[-debian-revision]
Описание (Description)
Version numbers as used for Debian binary and source packages
consist of three components. These are:
epoch This is a single (generally small) unsigned integer. It
may be omitted, in which case zero is assumed. If it is
omitted then the upstream-version may not contain any
colons.
It is provided to allow mistakes in the version numbers of
older versions of a package, and also a package's previous
version numbering schemes, to be left behind.
upstream-version
This is the main part of the version number. It is
usually the version number of the original ('upstream')
package from which the .deb file has been made, if this is
applicable. Usually this will be in the same format as
that specified by the upstream author(s); however, it may
need to be reformatted to fit into the package management
system's format and comparison scheme.
The comparison behavior of the package management system
with respect to the upstream-version is described below.
The upstream-version portion of the version number is
mandatory.
The upstream-version may contain only alphanumerics ('A-
Za-z0-9') and the characters . + - : ~ (full stop, plus,
hyphen, colon, tilde) and should start with a digit. If
there is no debian-revision then hyphens are not allowed;
if there is no epoch then colons are not allowed.
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 'debianization' of it and therefore no
revision indication is required.
It is conventional to restart the debian-revision at '1'
each 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).
Sorting algorithm
The upstream-version and debian-revision parts are compared by
the package management system using the same algorithm:
The strings are compared from left to right.
First the initial part of each string consisting entirely of non-
digit characters is determined. These two parts (one of which
may be empty) are compared lexically. If a difference is found
it is returned. The lexical comparison is a comparison of ASCII
values modified so that all the letters sort earlier than all the
non-letters and so that a tilde sorts before anything, even the
end of a part. For example, the following parts are in sorted
order: '~~', '~~a', '~', the empty part, 'a'.
Then the initial part of the remainder of each string which
consists entirely of digit characters is determined. The
numerical values of these two parts are compared, and any
difference found is returned as the result of the comparison.
For these purposes an empty string (which can only occur at the
end of one or both version strings being compared) counts as
zero.
These two steps (comparing and removing initial non-digit strings
and initial digit strings) are repeated until a difference is
found or both strings are exhausted.
Note that the purpose of epochs is to allow us to leave behind
mistakes in version numbering, and to cope with situations where
the version numbering scheme changes. It is not intended to cope
with version numbers containing strings of letters which the
package management system cannot interpret (such as 'ALPHA' or
'pre-'), or with silly orderings.
Примечание (Note)
The tilde character and its special sorting properties were
introduced in dpkg 1.10 and some parts of the dpkg build scripts
only gained support for it later in the 1.10.x series.
Смотри также (See also)
deb-control(5), deb(5), dpkg(1)
