Provided by: dselect_1.18.4ubuntu1_amd64 bug

NAME

       dselect - Debian package management frontend

SYNOPSIS

       dselect [option...] [command...]

DESCRIPTION

       dselect is one of the primary user interfaces for managing packages on a Debian system. At
       the dselect main menu, the system administrator can:
        - Update the list of available package versions,
        - View the status of installed and available packages,
        - Alter package selections and manage dependencies,
        - Install new packages or upgrade to newer versions.

       dselect operates as a front-end to dpkg(1), the low-level debian package handling tool. It
       features  a  full-screen  package  selections  manager  with package depends and conflicts
       resolver. When run with administrator privileges, packages can be installed, upgraded  and
       removed.  Various  access  methods can be configured to retrieve available package version
       information and installable packages from package repositories.   Depending  on  the  used
       access  method,  these  repositories  can be public archive servers on the internet, local
       archive servers or cdroms.  The recommended access method is apt, which is provided by the
       package apt.

       Normally dselect is invoked without parameters. An interactive menu is presented, offering
       the user a list of commands. If a command is given  as  argument,  then  that  command  is
       started  immediately.  Several  command  line parameters are still available to modify the
       running behaviour of dselect or show additional information about the program.

OPTIONS

       All options can be specified both on the command line and  in  the  dselect  configuration
       file    /etc/dpkg/dselect.cfg    or    the    files   on   the   configuration   directory
       /etc/dpkg/dselect.cfg.d/. Each line in the configuration file is either an option (exactly
       the  same  as  the  command  line  option but without leading hyphens) or a comment (if it
       starts with a ‘#’).

       --admindir directory
              Changes the directory where the dpkg ‘status’, ‘available’ and  similar  files  are
              located.   This  defaults to /var/lib/dpkg and normally there shouldn't be any need
              to change it.

       -Dfile, --debug file
              Turn on debugging. Debugging information is sent to file.

       --expert
              Turns on expert mode, i.e. doesn't display possibly annoying help messages.

       --colour|--color screenpart:[foreground],[background][:attr[+attr]...]
              Configures screen colors. This works only if your display  supports  colors.   This
              option  may  be  used  multiple  times  (and is best used in dselect.cfg). Each use
              changes the color (and optionally, other attributes) of one  part  of  the  screen.
              The parts of the screen (from top to bottom) are:

              title  The screen title.

              listhead
                     The header line above the list of packages.

              list   The scrolling list of packages (and also some help text).

              listsel
                     The selected item in the list.

              pkgstate
                     In  the  list  of  packages,  the  text indicating the current state of each
                     package.

              pkgstatesel
                     In the list of packages, the  text  indicating  the  current  state  of  the
                     currently selected package.

              infohead
                     The header line that displays the state of the currently selected package.

              infodesc
                     The package's short description.

              info   Used to display package info such as the package's description.

              infofoot
                     The last line of the screen when selecting packages.

              query  Used to display query lines

              helpscreen
                     Color of help screens.

              After  the  part  of  the screen comes a colon and the color specification. You can
              specify either the foreground color, the background color, or both, overriding  the
              compiled-in colors. Use standard curses color names.

              Optionally,  after  the  color  specification  is  another  colon, and an attribute
              specification. This is a list of one or more attributes, separated  by  plus  (‘+’)
              characters.   Available  attributes  include  (not  all  of  these will work on all
              terminals): normal, standout, underline, reverse, blink, bright, dim, bold

       -?, --help
              Print a brief help text and exit successfully.

       --version
              Print version information and exit successfully.

COMMANDS

       When dselect is started it can perform the following commands, either directly if  it  was
       specified  on  the command line or by prompting the user with a menu of available commands
       if running interactively:

   access
       Choose and configure an access method to access package repositories.

       By default, dselect provides several methods such  as  cdrom,  multi_cd,  nfs,  multi_nfs,
       harddisk,  mounted,  multi_mount, floppy or ftp, but other packages may provide additional
       methods, eg. the apt access method provided by the apt package.

       The use of the apt access method is strongly recommended.

   update
       Refresh the available packages database.

       Retrieves a list of available package versions from the package repository, configured for
       the  current  access  method, and update the dpkg database. The package lists are commonly
       provided by the repository as files named Packages or Packages.gz.   These  files  can  be
       generated by repository maintainers, using the program dpkg-scanpackages(1).

       Details  of the update command depend on the access method's implementation.  Normally the
       process is straightforward and requires no user interaction.

   select
       View or manage package selections and dependencies.

       This is the main function of dselect. In the select screen, the user can review a list  of
       all  available  and installed packages. When run with administrator privileges, it is also
       possible to interactively change packages selection state. dselect tracks the implications
       of these changes to other depending or conflicting packages.

       When  a  conflict  or  failed  depends  is  detected, a dependency resolution subscreen is
       prompted to the user. In this screen, a list  of  conflicting  or  depending  packages  is
       shown,  and  for  each  package  listed, the reason for its listing is shown. The user may
       apply the suggestions proposed by dselect, override them, or back  out  all  the  changes,
       including the ones that created the unresolved depends or conflicts.

       The  use  of  the  interactive  package  selections management screen is explained in more
       detail below.

   install
       Installs selected packages.

       The configured access method will  fetch  installable  or  upgradable  packages  from  the
       relevant  repositories  and  install these using dpkg.  Depending on the implementation of
       the access method, all packages can be prefetched before  installation,  or  fetched  when
       needed.  Some access methods may also remove packages that were marked for removal.

       If an error occurred during install, it is usually advisable to run install again. In most
       cases, the problems will disappear or be solved.  If problems persist or the  installation
       performed  was incorrect, please investigate into the causes and circumstances, and file a
       bug in the Debian bug tracking system. Instructions on how to do  this  can  be  found  at
       https://bugs.debian.org/  or  by  reading the documentation for bug(1) or reportbug(1), if
       these are installed.

       Details of the install command depend on the access method's implementation.   The  user's
       attention  and  input  may  be  required  during installation, configuration or removal of
       packages. This depends on the maintainer scripts in the package. Some packages make use of
       the debconf(1) library, allowing for more flexible or even automated installation setups.

   config
       Configures any previously installed, but not fully configured packages.

   remove
       Removes or purges installed packages, that are marked for removal.

   quit
       Quit dselect.

       Exits the program with zero (successful) errorcode.

PACKAGE SELECTIONS MANAGEMENT

   Introduction
       dselect  directly  exposes  the  administrator  to  some of the complexities involved with
       managing large sets of packages with many interdependencies. For a user who is  unfamiliar
       with  the  concepts  and the ways of the debian package management system, it can be quite
       overwhelming. Although dselect is aimed at easing package management  and  administration,
       it  is  only instrumental in doing so and can not be assumed to be a sufficient substitute
       for administrator skill and understanding. The user is required to be  familiar  with  the
       concepts  underlying  the  Debian packaging system.  In case of doubt, consult the dpkg(1)
       manpage and the Debian Policy manual, contained in the debian-policy package.

       Unless dselect is run in expert or immediate mode, a help screen is first  displayed  when
       choosing  this  command  from  the  menu. The user is strongly advised to study all of the
       information presented in the online help screens, when  one  pops  up.   The  online  help
       screens can at any time be invoked with the ‘?’ key.

   Screen layout
       The  select  screen  is by default split in a top and a bottom half.  The top half shows a
       list of packages. A cursor bar can select an individual package, or a group  of  packages,
       if  applicable,  by  selecting  the group header. The bottom half of the screen shows some
       details about the package currently selected in the top half of the screen.  The  type  of
       detail that is displayed can be varied.

       Pressing  the ‘I’ key toggles a full-screen display of the packages list, an enlarged view
       of the package details, or the equally split screen.

   Package details view
       The package details view by default shows the extended package description for the package
       that is currently selected in the packages status list.  The type of detail can be toggled
       by pressing the ‘i’ key.  This alternates between:
        - the extended description
        - the control information for the installed version
        - the control information for the available version

       In a dependency resolution screen, there is also the possibility of viewing  the  specific
       unresolved depends or conflicts related to the package and causing it to be listed.

   Packages status list
       The  main  select  screen  displays  a  list  of  all packages known to the debian package
       management system. This includes packages installed on the system and packages known  from
       the available packages database.

       For  every  package, the list shows the package's status, priority, section, installed and
       available architecture, installed and available versions, the package name and  its  short
       description,  all  in one line.  By pressing the ‘A’ key, the display of the installed and
       available architecture can be toggled between on an off.  By pressing  the  ‘V’  key,  the
       display  of  the  installed  and  available  version can be toggled between on an off.  By
       pressing the ‘v’ key, the package status display is toggled between verbose and shorthand.
       Shorthand display is the default.

       The  shorthand  status  indication  consists  of  four  parts: an error flag, which should
       normally be clear, the current status, the last selection state and the current  selection
       state.  The first two relate to the actual state of the package, the second pair are about
       the selections set by the user.

       These are the meanings of the shorthand package status indicator codes:
        Error flag:
         empty   no error
         R       serious error, needs reinstallation;
        Installed state:
         empty   not installed;
         *       fully installed and configured;
         -       not installed but some config files may remain;
         U       unpacked but not yet configured;
         C       half-configured (an error happened);
         I       half-installed (an error happened).
        Current and requested selections:
         *       marked for installation or upgrade;
         -       marked for removal, configuration files remain;
         =       on hold: package will not be processed at all;
         _       marked for purge, also remove configuration;
         n       package is new and has yet to be marked.

   Cursor and screen movement
       The package selection list and the dependency conflict resolution screens can be navigated
       using motion commands mapped to the following keys:
         p, Up, k           move cursor bar up
         n, Down, j         move cursor bar down
         P, Pgup, Backspace scroll list 1 page up
         N, Pgdn, Space     scroll list 1 page down
         ^p                 scroll list 1 line up
         ^n                 scroll list 1 line down
         t, Home            jump to top of list
         e, End             jump to end of list
         u                  scroll info 1 page up
         d                  scroll info 1 page down
         ^u                 scroll info 1 line up
         ^d                 scroll info 1 line down
         B, Left-arrow      pan display 1/3 screen left
         F, Right-arrow     pan display 1/3 screen right
         ^b                 pan display 1 character left
         ^f                 pan display 1 character right

   Searching and sorting
       The  list  of  packages can be searched by package name. This is done by pressing ‘/’, and
       typing a simple search string. The string is interpreted as a regex(7) regular expression.
       If  you  add  ‘/d’ to the search expression, dselect will also search in descriptions.  If
       you add ‘/i’ the search will be case insensitive.  You may combine these two suffixes like
       this:  ‘/id’.   Repeated  searching  is accomplished by repeatedly pressing the ‘n’ or ‘\’
       keys, until the wanted package is found.  If the search reaches the bottom of the list, it
       wraps to the top and continues searching from there.

       The  list  sort  order  can  be  varied  by pressing the ‘o’ and ‘O’ keys repeatedly.  The
       following nine sort orderings can be selected:
        alphabet          available           status
        priority+section  available+priority  status+priority
        section+priority  available+section   status+section
       Where not listed above explicitly, alphabetic order is used as the final subordering  sort
       key.

   Altering selections
       The  requested  selection  state  of individual packages may be altered with the following
       commands:
         +, Insert    install or upgrade
         =, H         hold in present state and version
         :, G         unhold: upgrade or leave uninstalled
         -, Delete    remove, but leave configuration
         _            remove & purge configuration

       When the change request results in one or more unsatisfied depends or  conflicts,  dselect
       prompts  the  user  with  a  dependency  resolution screen. This will be further explained
       below.

       It is also possible to apply these commands to groups of package selections,  by  pointing
       the  cursor  bar  onto  a group header. The exact grouping of packages is dependent on the
       current list ordering settings.

       Proper care should be taken when altering large groups of  selections,  because  this  can
       instantaneously create large numbers of unresolved depends or conflicts, all of which will
       be listed in one dependency resolution  screen,  making  them  very  hard  to  handle.  In
       practice, only hold and unhold operations are useful when applied to groups.

   Resolving depends and conflicts
       When  the  change request results in one or more unsatisfied depends or conflicts, dselect
       prompts the user with a dependency resolution screen. First however, an  informative  help
       screen is displayed.

       The  top  half  of this screen lists all the packages that will have unresolved depends or
       conflicts, as a result of the requested change, and all the  packages  whose  installation
       can  resolve  any of these depends or whose removal can resolve any of the conflicts.  The
       bottom half defaults to show the depends or conflicts that cause  the  currently  selected
       package to be listed.

       When  the  sublist  of  packages  is displayed initially, dselect may have already set the
       requested selection status of some of the listed packages, in order to resolve the depends
       or  conflicts that caused the dependency resolution screen to be displayed. Usually, it is
       best to follow up the suggestions made by dselect.

       The listed packages' selection state may be reverted to the  original  settings,  as  they
       were before the unresolved depends or conflicts were created, by pressing the ‘R’ key.  By
       pressing the ‘D’ key, the automatic suggestions are reset, but the change that caused  the
       dependency  resolution  screen  to be prompted is kept as requested.  Finally, by pressing
       ‘U’, the selections are again set to the automatic suggestion values.

   Establishing the requested selections
       By pressing enter, the currently displayed set  of  selections  is  accepted.  If  dselect
       detects  no unresolved depends as a result of the requested selections, the new selections
       will be set.  However, if there are any unresolved depends, dselect will again prompt  the
       user with a dependency resolution screen.

       To  alter  a  set  of  selections that creates unresolved depends or conflicts and forcing
       dselect to accept it, press the ‘Q’ key. This sets the  selections  as  specified  by  the
       user, unconditionally. Generally, don't do this unless you've read the fine print.

       The  opposite  effect,  to  back  out  any  selections  change requests and go back to the
       previous list of selections, is attained by pressing the ‘X’ or escape keys. By repeatedly
       pressing  these keys, any possibly detrimental changes to the requested package selections
       can be backed out completely to the last established settings.

       If you mistakenly establish some settings and wish to revert all the selections to what is
       currently  installed  on the system, press the ‘C’ key.  This is somewhat similar to using
       the unhold command on all packages, but provides a more  obvious  panic  button  in  cases
       where the user pressed enter by accident.

ENVIRONMENT

       HOME   If  set,  dselect will use it as the directory from which to read the user specific
              configuration file.

BUGS

       The dselect package selection interface is confusing to some new  users.   Reportedly,  it
       even makes seasoned kernel developers cry.

       The documentation is lacking.

       There is no help option in the main menu.

       The visible list of available packages cannot be reduced.

       The  built  in access methods can no longer stand up to current quality standards. Use the
       access method provided by apt, it is not only not broken, it is also  much  more  flexible
       than the built in access methods.

SEE ALSO

       dpkg(1), apt-get(8), sources.list(5), deb(5).