1 files changed, 153 insertions, 0 deletions
diff --git a/man/deb-version.pod b/man/deb-version.pod
new file mode 100644
index 0000000..8944358
--- /dev/null
+++ b/man/deb-version.pod
@@ -0,0 +1,153 @@
+# dpkg manual page - deb-version(7)
+#
+# Copyright © 1996-1998 Ian Jackson and Christian Schwarz
+#   for parts of the text reused from the Debian Policy
+# Copyright © 2007 Frank Lichtenheld <djpig@debian.org>
+# Copyright © 2011, 2013, 2015 Guillem Jover <guillem@debian.org>
+#
+# This is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+=encoding utf8
+
+=head1 NAME
+
+deb-version - Debian package version number format
+
+=head1 SYNOPSIS
+
+[I<epoch>B<:>]I<upstream-version>[B<->I<debian-revision>]
+
+=head1 DESCRIPTION
+
+Version numbers as used for Debian binary and source packages
+consist of three components. These are:
+
+=over
+
+=item I<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 I<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.
+
+=item I<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 I<.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 I<upstream-version> is
+described below. The I<upstream-version>
+portion of the version number is mandatory.
+
+The I<upstream-version> may contain only
+alphanumerics (“A-Za-z0-9”) and the characters
+B<.> B<+> B<-> B<:> B<~>
+(full stop, plus, hyphen, colon, tilde) and should
+start with a digit.  If there is no
+I<debian-revision> then hyphens are not allowed;
+if there is no I<epoch> then colons are not
+allowed.
+
+=item I<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
+B<+> B<.> B<~>
+(plus, full stop, tilde) and is
+compared in the same way as the
+I<upstream-version> is.
+
+It is optional; if it isn't present then the
+I<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
+I<debian-revision> at ‘1’ each time the
+I<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 I<upstream-version> and
+I<debian-revision>. The absence of a
+I<debian-revision> compares earlier than the
+presence of one (but note that the I<debian-revision>
+is the least significant part of the version number).
+
+=back
+
+=head2 Sorting algorithm
+
+The I<upstream-version> and I<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
+B<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.
+
+=head1 NOTES
+
+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.
+
+=head1 SEE ALSO
+
+B<deb-control>(5),
+B<deb>(5),
+B<dpkg>(1)