LinuxGuruz
  • Last 5 Forum Topics
    Replies
    Views
    Last post


The Web Only This Site
  • BOOKMARK

  • ADD TO FAVORITES

  • REFERENCES


  • MARC

    Mailing list ARChives
    - Search by -
     Subjects
     Authors
     Bodies





    FOLDOC

    Computing Dictionary




  • Text Link Ads






  • LINUX man pages
  • Linux Man Page Viewer


    The following form allows you to view linux man pages.

    Command:

    dpkg-maintscript-helper

    
    
    
    

    SYNOPSIS

           dpkg-maintscript-helper command [parameter...] --  maint-script-parame-
           ter...
    
    
    

    COMMANDS AND PARAMETERS

           rm_conffile conffile [lastversion [package]]
    
           mv_conffile oldconffile newconffile [lastversion [package]]
    
    
    

    DESCRIPTION

           This program is designed to be run within maintainer scripts to achieve
           some tasks that dpkg can't (yet)  handle  natively  either  because  of
           design decisions or due to current limitations.
    
           Many of those tasks require coordinated actions from several maintainer
           scripts (preinst, postinst, prerm, postrm). To avoid mistakes the  same
           call  simply  needs to be put in all scripts and the program will auto-
           matically  adapt  its  behaviour  based  on  the  environment  variable
           DPKG_MAINTSCRIPT_NAME  and on the maintainer scripts arguments that you
           have to forward after a double dash.
    
    
    

    CONFFILE RELATED TASKS

           When upgrading a package, dpkg will not automatically remove a conffile
           (a  configuration  file for which dpkg should preserve user changes) if
           it is not present in the newer version. There are two principal reasons
           for this; the first is that the conffile could've been dropped by acci-
           dent and the next version could restore it, users wouldn't  want  their
           changes  thrown  away.  The  second  is to allow packages to transition
           files from a dpkg-maintained conffile to a file maintained by the pack-
           age's maintainer scripts, usually with a tool like debconf or ucf.
    
           This  means  that  if a package is intended to rename or remove a conf-
           file, it must explicitly do so and dpkg-maintscript-helper can be  used
           to  implement  graceful  deletion  and moving of conffiles within main-
           tainer scripts.
    
       REMOVING A CONFFILE
           If a conffile is completely removed, it should be  removed  from  disk,
           unless the user has modified it. If there are local modifications, they
           should be preserved. If the package upgrades aborts, the newly obsolete
           conffile should not disappear.
    
           All  of  this  is implemented by putting the following shell snippet in
           the preinst, postinst and postrm maintainer scripts:
    
               dpkg-maintscript-helper rm_conffile \
                   conffile lastversion package -- "$@"
    
           conffile is the filename of the conffile to remove.  lastversion is the
           last  version  of  the package that contained the conffile (or the last
           version of the package that did not take care to  remove  the  obsolete
           now.
    
       RENAMING A CONFFILE
           If  a  conffile is moved from one location to another, you need to make
           sure you move across any changes the user has made.  This  may  seem  a
           simple  change to the preinst script at first, however that will result
           in the user being prompted by dpkg to approve the conffile  edits  even
           though they are not responsible of them.
    
           Graceful  renaming  can  be  implemented by putting the following shell
           snippet in the preinst, postinst and postrm maintainer scripts:
    
               dpkg-maintscript-helper mv_conffile \
                   oldconffile newconffile lastversion package -- "$@"
    
           oldconffile and newconffile are the old and new name of the conffile to
           rename.  lastversion  is the last version of the package that contained
           the conffile with the old name. If lastversion  is  empty  or  omitted,
           then  the operation is tried on every upgrade (note: it's safer to give
           the version and have the operation tried only  once).  package  is  the
           package    name,    it's    optional    as    it    will   default   to
           $DPKG_MAINTSCRIPT_PACKAGE (this variable is set by dpkg to the name  of
           the  package  acted upon). All the parameters of the maintainer scripts
           have to be forwarded to the program after "--".
    
           Current implementation: the preinst checks if  the  conffile  has  been
           modified,  if yes it's left on place otherwise it's renamed to oldconf-
           file.dpkg-remove.  On  configuration,  the  postinst  removes  oldconf-
           file.dpkg-remove  and renames oldconffile to newconffile if oldconffile
           is still available. On abort-upgrade/abort-install, the postrm  renames
           oldconffile.dpkg-remove back to oldconffile if required.
    
    
    

    INTEGRATION IN PACKAGES

           Given  that  dpkg-maintscript-helper  is  used in the preinst, using it
           unconditionally requires a pre-dependency to ensure that  the  required
           version  of dpkg has been unpacked before. The required version depends
           on the command used, for rm_conffile and mv_conffile it is 1.15.7.2:
    
               Pre-Depends: dpkg (>= 1.15.7.2)
    
           But in many cases the operation done by the program is not critical for
           the package, and instead of using a pre-dependency we can call the pro-
           gram only if we know that the required command is supported by the cur-
           rently installed dpkg:
    
               if dpkg-maintscript-helper supports command; then
                   dpkg-maintscript-helper command ...
               fi
    
    
    

    AUTHORS

           Copyright (C) 2010 Raphael Hertzog
           Copyright (C) 2008 Joey Hess
    
  • MORE RESOURCE


  • Linux

    The Distributions





    Linux

    The Software





    Linux

    The News



  • MARKETING






  • Toll Free

webmaster@linuxguruz.com
Copyright © 1999 - 2016 by LinuxGuruz