NAME

       duck - the Debian Url ChecKer

SYNOPSIS

        duck  [ OPTION ]... [-f file] [-u file] [-c file]

DESCRIPTION

       duck extracts links, email address domains and VCS-* entries from the following files:

       o      debian/control

       o      debian/upstream, debian/upstream-metadata.yaml and debian/upstream/metadata

       o      debian/copyright

       o      DEP-3 patch files in every directory a series file is found

       o      systemd.unit  files  (*.socket,  *.device, *.mount, *.automount, *.swap, *.target, *.path, *.time,
              *.snapshot, *.slice, *.scope)

       o      Appstream files (*.appdata)

       It tries to access those VCS-* entries and URLs using the approriate tool to find out whether  the  given
       URLs  or  entries are broken or working. If errors are detected, the filename, fieldname and URL/email of
       the broken entry are displayed.

       duck will search for the default files (see above) and skip them silently, if they cannot be  found.   If
       specific filenames for options -c, -f or -u are given, and one of those files cannot be found, duck exits
       with exit code 2.

       Email  address domains are checked for existing MX records, A records, or AAAA records, in this order. If
       none of these 3 are found for a given domain, it is considered broken.

       Checks results are displayed with 3 different error levels

       O:     (OK) Indicates that the given check did not result in an error. Only shown if -n is used.

       I:     (Information) Indicates informational warnings, suchs as missing helper tools as well  as  failing
              checks based on searches in unstructured text files, which sometimes lead to false positives.

       E:     (Error)  Indicates  failing checks based on data from well-defined fields (e.g. Homepage: entry in
              debian/control).

       and 3 different certainty-levels

       certain
              Data taken from well defined fields. As the format of this field is specified (e.g. Debian Policy,
              etc.), it can be checked by the appropriate tools. If this check then fails, the data in the field
              is certainly erroneous.

       possible
              Data extracted using regular expressions (e.g. email addresses, URLs). This might  lead  to  false
              positives, so the check result is possibly a false positive.

       wild-guess
              Data  extracted  from  websites,  by  using  regular  expressions.  This is still experimental and
              probably buggy, hence the "wild-guess".

OPTIONS

       -v     verbose mode. This shows all URLs found and the checks run.

       -q     quiet mode. Suppress all output.

       -n     dry run. Don't run any checks, just show entries to be checked.

       --modules-dir=DIRECTORY
              specify modules directory.  Mostly  useful  for  developing  new  checks.  If  this  parameter  is
              specified,  only  modules defined in this directory are used. You have to copy all *.pm files from
              /usr/share/duck/lib/checks to the directory specified.

       --no-color
              do not colorize output. See also the DUCK_NOCOLOR environment variable.

       --no-https
              do not try to find matching https URLs  to  http  URLs.  See  also  the  DUCK_NOHTTPS  environment
              variable.

       --missing-helpers
              display list of missing external helper tools and exits.

       --version
              display copyright and version information

       -f     specify path to control file. This overrides the default debian/control.

       -F     skip processing of the control file.

       -u     specify  path  to  upstream  metadata  file.  This  overrides  the  default files debian/upstream,
              debian/upstream-metadata.yaml and debian/upstream/metadata.

       -U     skip processing of the upstream metadata file.

       -c     specify path to copyright file. This overrides the default debian/copyright.

       -C     skip processing of copyright file.

       -P     skip processing of patch files.

       -A     skip processing of appstream metadata files.

       -S     skip processing of systemd.unit files.

ENVIRONMENT VARIABLES

       DUCK_NOCOLOR
              If this variable is set, do not colorize output.

       DUCK_NOHTTPS
              If this variable is set, do not try to find matching https URLs to http URLs.

CHECK MODULES

EXAMPLE

       To run duck, change your working directory to an extracted debian source package and run:
        duck

EXIT STATUS

       0      Success, no errors

       1      Error(s) detected

       2      User-specified file not found

SEE ALSO

       Please see http://duck.debian.net/ for additional information as well as an overview of duck  checks  run
       on all source packages in Debian/unstable.

                                                   2014-10-23                                            DUCK(1)