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dpkg::changelog::parse(3) [linux man page]

Dpkg::Changelog::Parse(3)					   libdpkg-perl 					 Dpkg::Changelog::Parse(3)

Dpkg::Changelog::Parse - generic changelog parser for dpkg-parsechangelog DESCRIPTION
This module provides a single function changelog_parse() which reproduces all the features of dpkg-parsechangelog. Functions my $fields = changelog_parse(%opt) This function will parse a changelog. In list context, it return as many Dpkg::Control object as the parser did output. In scalar context, it will return only the first one. If the parser didn't return any data, it will return an empty in list context or undef on scalar context. If the parser failed, it will die. The parsing itself is done by an external program (searched in the following list of directories: $opt{libdir}, /usr/local/lib/dpkg/parsechangelog, /usr/lib/dpkg/parsechangelog) That program is named according to the format that it's able to parse. By default it's either "debian" or the format name lookep up in the 40 last lines of the changelog itself (extracted with this perl regular expression "schangelog-format:s+([0-9a-z]+)W"). But it can be overridden with $opt{changelogformat}. The program expects the content of the changelog file on its standard input. The changelog file that is parsed is debian/changelog by default but it can be overridden with $opt{file}. All the other keys in %opt are forwarded as parameter to the external parser. If the key starts with "-", it's passed as is. If not, it's passed as "--<key>". If the value of the corresponding hash entry is defined, then it's passed as the parameter that follows. 2012-04-17 Dpkg::Changelog::Parse(3)

Check Out this Related Man Page

dpkg-parsechangelog(1)						    dpkg suite						    dpkg-parsechangelog(1)

       dpkg-parsechangelog - parse Debian changelog files

       dpkg-parsechangelog [option...]

       dpkg-parsechangelog  reads  and parses the changelog of an unpacked Debian source tree and outputs the information in it to standard output
       in a machine-readable form.

       -l, --file changelog-file
	      Specifies the changelog file to read information from.  A '-' can be used to specify reading from standard input.   The  default	is

       -F changelog-format
	      Specifies the format of the changelog. By default the format is read from a special line near the bottom of the changelog or failing
	      that defaults to the debian standard format. See also CHANGELOG FORMATS.

       -L libdir
	      Obsolete option without effect (since dpkg 1.18.8).  Setting the perl environment variables PERL5LIB or PERLLIB has a similar effect
	      when looking for the parser perl modules.

       -S, --show-field field
	      Specifies the name of the field to show (since dpkg 1.17.0).  The field name is not printed, only its value.

       -?, --help
	      Show the usage message and exit.

	      Show the version and exit.

   Parser Options
       The following options can be used to influence the output of the changelog parser, e.g. the range of entries or the format of the output.

       --format output-format
	      Set  the	output format. Currently supported values are dpkg and rfc822.	dpkg is the classic output format (from before this option
	      existed) and the default. It consists of one paragraph in Debian control format (see deb-control(5)). If	more  than  one  entry	is
	      requested, then most fields are taken from the most recent entry, except otherwise stated:

	      Source: pkg-name

	      Version: version

	      Distribution: target-distribution

	      Urgency: urgency
		     The  highest  urgency  of	all included entries is used, followed by the concatenated (space-separated) comments from all the
		     versions requested.

	      Maintainer: author

	      Date: date
		     The date of the entry as a string, as it appears in the changelog.  With a strptime(3) format "%a, %d %b %Y %T %z", but where
		     the  day  of the week might not actually correspond to the real day obtained from the rest of the date string.  If you need a
		     more accurate representation of the date, use the Timestamp field, but take into account it might not be possible to  map	it
		     back to the exact value in this field.

	      Timestamp: timestamp
		     The date of the entry as a timestamp in seconds since the epoch (since dpkg 1.18.8).

	      Closes: bug-number
		     The Closes fields of all included entries are merged.

	      Changes: changelog-entries
		     The  text	of  all  changelog entries is concatenated. To make this field a valid Debian control format multiline field empty
		     lines are replaced with a single full stop and all lines is intended by one space character. The exact content depends on the
		     changelog format.

	      The Version, Distribution, Urgency, Maintainer and Changes fields are mandatory.

	      There might be additional user-defined fields present.

	      The rfc822 format uses the same fields but outputs a separate paragraph for each changelog entry so that all metadata for each entry
	      is preserved.

       --all  Include all changes. Note: other options have no effect when this is in use.

       -s, --since version
       -v version
	      Include all changes later than version.

       -u, --until version
	      Include all changes earlier than version.

       -f, --from version
	      Include all changes equal or later than version.

       -t, --to version
	      Include all changes up to or equal than version.

       -c, --count number
       -n number
	      Include number entries from the top (or the tail if number is lower than 0).

       -o, --offset number
	      Change the starting point for --count, counted from the top (or the tail if number is lower than 0).

       It is possible to use a different format to the standard one, by providing a parser for that alternative format.

       In order to have dpkg-parsechangelog run the new parser, a line must be included within the last 40 lines of the changelog  file,  matching
       the Perl regular expression: "schangelog-format:s+([0-9a-z]+)W".  The part in parentheses should be the name of the format. For example:

	      @@@ changelog-format: otherformat @@@

       Changelog format names are non-empty strings of alphanumerics.

       If  such  a line exists then dpkg-parsechangelog will look for the parser as a Dpkg::Changelog::Otherformat perl module; it is an error for
       it not being present.  The parser name in the perl module will be automatically capitalized.  The default changelog format is debian, and a
       parser for it is provided by default.

       The parser should be derived from the Dpkg::Changelog class and implement the required documented interface.

       If  the	changelog  format  which  is being parsed always or almost always leaves a blank line between individual change notes, these blank
       lines should be stripped out, so as to make the resulting output compact.

       If the changelog format does not contain date or package name information this information should be omitted from the  output.  The  parser
       should not attempt to synthesize it or find it from other sources.

       If  the	changelog  does  not  have  the  expected  format  the	parser should error out, rather than trying to muddle through and possibly
       generating incorrect output.

       A changelog parser may not interact with the user at all.

       All Parser Options except for -v are only supported since dpkg 1.14.16.

       Short option parsing with non-bundled values available only since dpkg 1.18.0.

	      The changelog file, used to obtain version-dependent information about the source package, such as the urgency and  distribution	of
	      an upload, the changes made since a particular release, and the source version number itself.

       deb-changelog(5).							    2018-04-16						    dpkg-parsechangelog(1)

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