NAME

       dpkg-mergechangelogs - 3-way merge of debian/changelog files

SYNOPSIS

       dpkg-mergechangelogs [option...] old new-a new-b [out]

DESCRIPTION

       This  program  will  use  the  3 provided versions of the Debian changelog to generate a merged changelog
       file. The resulting changelog is stored in the file  out  or  output  to  the  standard  output  if  that
       parameter is not given.

       Each  entry  is  identified  by  its  version number and they are assumed to be not conflicting, they are
       simply merged in the right order (by decreasing version number). When --merge-prereleases  is  used,  the
       part  of  the  version  number  after  the  last  tilde  is dropped so that 1.0-1~exp1 and 1.0-1~exp5 are
       considered to be the same entry. When the same version is available in both new-a and new-b,  a  standard
       line-based  3-way  merge is attempted (provided that the module Algorithm::Merge is available — it's part
       of the package libalgorithm-merge-perl — otherwise you get a  global  conflict  on  the  content  of  the
       entry).

OPTIONS

       --merge-prereleases, -m
              Drop the part after the last tilde in the version number when doing version comparison to identify
              if two entries are supposed to be the same or not.

              This is useful when you keep using the same changelog entry but you increase  its  version  number
              regularly.  For  instance,  you  might have 2.3-1~exp1, 2.3-1~exp2, ... until the official release
              2.3-1 and they are all the same changelog entry that has evolved over time.

       --help Show the usage message and exit.

       --version
              Show the version and exit.

LIMITATIONS

       Anything that is not parsed by Dpkg::Changelog is lost during the merge.  This might include  stuff  like
       vim modelines, comments which were not supposed to be there, etc.

INTEGRATION WITH GIT

       If  you  want  to use this program to merge Debian changelog files in a git repository, you have first to
       register a new merge driver in .git/config or ~/.gitconfig:

        [merge "dpkg-mergechangelogs"]
            name = debian/changelog merge driver
            driver = dpkg-mergechangelogs -m %O %A %B %A

       Then you have to setup the merge attribute for the debian/changelog file either in .gitattributes in  the
       repository itself, or in .git/info/attributes:

        debian/changelog merge=dpkg-mergechangelogs