man > DUCK(1)

DUCK(1)                                General Commands Manual                               DUCK(1)

NAME
       duck - the Debian Url ChecKer

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

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)

       If an URL is supplied, duck uses dget to download the specified URL and processes  the  down‐
       loaded source package (*.dsc file) instead of working on the current directory.

       It  tries  to  access  those  VCS-*  entries  and URLs using the appropriate tool to find out
       whether the given URLs or entries are broken or working. If errors are  detected,  the  file‐
       name, 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 can‐
       not 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.  Home‐
              page: 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
       -n     dry run. Don't run any checks, just show entries to be checked.

       -q     quiet mode. Suppress all output.

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

       --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.

       --color=[WHEN]
              Specify when to emit escape sequences to the output. Available options are:

                      auto  Emit color escape codes on STDOUT/STDERR, no color if output is piped to
                      a file or the current terminal is not capable of displaying colors.




                      always Always emit color escape codes.




                      never Never emit color escape codes.




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

       --no-check-certificate
                      do not check if SSL certificates autenticity. This is highly discouraged!

       --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  de‐
                      bian/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.

       -l filename    Process  URLs, email addresses, git:// and svn:// entries from the file speci‐
                      fied. Specify one entry per line. This also disables all other  check  modules
                      searching for entries in various files.


       --disable-urlfix=<fix1,...>
                      disables the specified url fix(es). An urlfix tries to remove leading/trailing
                      characters  from extracted URLs, like trailing dots or parentheses. Using this
                      parameter enables all urlfixes minus the specified ones.


       --enable-urlfix=<fix1,...>
                      enables the specified url fix(es). Using this parameter disabled all  urlfixes
                      minus the specified ones.


                      The following urlfixes are available:

                      TRAILING_COLON Removes trailing colon ":" character.



                      TRAILING_PAREN_DOT Removes the string ")." from the end of the URL.


                      TRAILING_PUNCTUATION Removes trailing "." and "," characters.


                      TRAILING_QUOTES  Removes  trailing  single quotes "'" characters. Note: Double
                      quotes (") are already correctly handled by the used perl regex matchers.


                      TRAILING_SLASH_DOT Removes the string "/." (without the quotes) from  the  end
                      of the URL.


                      TRAILING_SLASH_PAREN Removes the string "/)" (without the quotes) from the end
                      of the URL.


       --tasks=[number]
                      Specify  the number of checks allowed to run in parallel. Default value is 24.
                      This value must be an integer value >0.


       All urlfixes are enabled by default.





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

       XDG_CONFIG_HOME
              if this variable is set, use the config file (if  any)  $XDG_HOME/duck/duck.conf.  The
              default value is $HOME/.config/duck/duck.conf .

       XDG_CONFIG_DIRS
              defines  the  preference-ordered  set  of base directories to search for configuration
              files in addition to the XDG_CONFIG_HOME base directory. The directories  in  XDG_CON‐
              FIG_DIRS should be separated with a colon ':'.




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


FILES
       debian/duck-overrides
              Overrides-file  in  the  Debian package source tree. This files contains a list of URL
              regexs which should not be reported as down/broken. This might  be  useful  in  cases,
              where  URLs  are  extracted  from  old/outdated copyright-files or patches, which will
              never ever be working, and which will then lead to false positives. Please see an  ex‐
              ample in /usr/share/doc/duck/examples.

       duck.conf
              Config  file  which contains the regular expressions used to detect parked domains and
              redirected websites. The default file is in /etc/duck/duck.conf. duck also honors  the
              XDG  Base  Directory Specification, see the section ENVIRONMENT VARIABLES for details.
              Search order for duck.conf is:

              $XDG_CONFIG_HOME/duck/duck.conf (default: $HOME/.config/duck/duck.conf)

              /etc/duck/duck.conf

              /$XDG_CONFIG_DIRS (default: /etc/xdg/duck/duck.conf)

              Please see the  XDG  Base  Directory  Specification  (https://specifications.freedesk‐
              top.org/basedir-spec/basedir-spec-latest.html) for more details.


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.

                                             2017-08-10                                      DUCK(1)
DUCK(1) □✕
NAME SYNOPSIS DESCRIPTION
certain possible wild-guess
OPTIONS
-n dry run. Don't run any checks, just show entries to be checked. -q quiet mode. Suppress all output. -v verbose mode. This shows all URLs found and the checks run. --no-check-certificate --missing-helpers -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 de‐ -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. -l filename Process URLs, email addresses, git:// and svn:// entries from the file speci‐ --disable-urlfix= --enable-urlfix= --tasks=[number]
ENVIRONMENT VARIABLES EXAMPLE
duck
EXIT STATUS FILES SEE ALSO

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