JUKE(7)                                                   JUKE(7)

          juke - music jukebox

          juke [ -t ] [ -w ] [ -h srvhost ] [ -s srvname ]

          games/jukebox [ -t ] [ -w ]

          games/jukefs [ -m mountpoint ] [ -s srvname ] [ mapfile ]

          Jukebox controls a playlist server (see playlistfs(7))
          through a graphical user interface.  It connects to a music
          database server which reads a set of map files that describe
          recordings and their location.  Currently, there is one set
          of maps, mostly for classical music, with some jazz and
          other stuff thrown in.  These are served by jukefs, which
          presents a file system conventionally mounted at /mnt/juke.
          The playlist, explained below, is managed by a file system
          implemented by playlistfs(7) and normally mounted on /mnt.

          Jukebox is most easily started through the juke shell

          Jukebox has four windows, which can be selected by clicking
          the appropriate tab at the top of the window.

          Above the tab are nine buttons and a volume slider.  The
          buttons are named, from left to right, Exit, Pause, Play,
          Halt, Back, Forward, Root, Delete, and Help. The buttons are
          active when they are displayed in dark green (or red).  When
          they are pale blue they are inactive. The Exit button is
          always active; it exits the program (but leaves the playlist
          and music database servers running).

          The browse window is for browsing through the music and
          selecting music to play.  Browsing down in the music hierar-
          chy is done by clicking button one on an item.  Clicking
          button three goes back up.  Clicking button two recursively
          adds all files below the selected item to the play list.

          The selected music is displayed in the playlist window.  The
          track currently playing is shown in the playing window.

          The Root button browses back to the root.

          The Delete button empties the playlist.

          The Help displays a minimal on-line manual.

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     JUKE(7)                                                   JUKE(7)

          Play starts playing at the beginning of the play list, or at
          the selected track in the play list.

          During play, Pause, Stop, Back, and Forward are active.
          Back and Forward go back or forward a track at a time.  The
          other buttons do the obvious thing.

          The -t flag chooses a tiny font, useful for handhelds.

          The -w flag creates the jukebox in a new window.  Normally,
          the jukebox takes over the window in which it is invoked.

          The -s flag specifies the name under which the file descrip-
          tors of the playlist and databse servers are posted in /srv.
          This allows two or more play list servers to exist on one
          platform, e.g., when there are several audio devices.  The
          default value of the flag is $user for a playlist server at
          /srv/playlistfs.$user and a database server at

          Jukefs reads a set of maps describing the music data, builds
          an in-memory database, and provides lookup service to
          jukebox. The default map is /sys/lib/music/map.  It consists
          of a hierarchical set of objects. Each object has a type, a
          value, zero or more attribute-value pairs and zero or more
          subobjects.    An object consists of the type, followed by
          its contents between curly brackets.  Attribute value pairs
          consist of a single line containing an attribute name, an
          equals sign, and a value.  The value of an object is any
          text not containing curly brackets or equals signs.  Here is
          an example:

          category {
               composer = mahler

               Gustav Mahler
               (1860 — 1911)

               work {
                    path {classic/mahler}
                    class = symphonic
                    orchestra = rfo
                    conductor = Waart,~Edo~de

                    Symphony Nº 5 in c♯ (RFO, Vienna)
                         Radio Filharmonisch Orkest Holland
                         Edo de Waart, conductor

                         recorded: Musikverein, Vienna, May 6, 1996

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     JUKE(7)                                                   JUKE(7)

                    command {number}
                    track {
                         Trauermarsch (In gemessenem Schritt. Streng. Wie ein Kondukt)
                         time {13:55}
                         file {034.pac}
                    track {
                         Stürmisch bewegt, mit größter Vehemenz
                         time {15:34}
                         file {035.pac}
                    track {
                         Scherzo (Kräftig, nicht zu schnell)
                         time {18:54}
                         file {036.pac}
                    track {
                         Adagietto (Sehr Langsam)
                         time {10:01}
                         file {037.pac}
                    track {
                         Rondo–Finale (Allegro)
                         time {15:44}
                         file {038.pac}

          This example shows a category object for the composer Gustav
          Mahler (the value consists of the two lines `Gustav Mahler'
          and `(1860 — 1911)') with one subobject, a work object whose
          value is `Symphony Nº 5 in c♯ (RFO, Vienna)'.  The work
          object contains six subobjects: one performance object and
          five track objects.

          Category objects must contain exactly one attribute-value
          pair.  The attribute names a subobject of the root under
          which this category object will be placed.  Gustav Mahler,
          thus, will be placed in Root→composer.  Work, Recording,
          Part, and Track, objects all describe named containers for
          subunits.  A Lyrics, Performance, or Soloists object adds
          information to a Work, Recording, Part, or Track, object.
          It should only contain text.  The same is true for a Time
          object; however, it should only be used adjacent to File
          objects and it should contain the running time of that file
          (this is for future use).

          A File object specifies a file to be played.  When the
          Select button is pressed, all file objects contained hierar-
          chically in the selected object are added to the playlist.

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     JUKE(7)                                                   JUKE(7)

          There are a number of pseudo objects: Command may contain
          either sort or number. The sort command sorts the subobjects
          of the object it appears in by key or textual content.  The
          number commands prepends numbers to the texts of its subob-
          jects (e.g., for the parts in a symphony)

          An Include object is replaced by the contents of the named

          A Key object specifies a key for sorting subobjects.

          Finally, a Path object specifies a path to be prepended to
          the files named in hierarchically contained File objects.

          The attribute-value value pairs arrange for entries to be
          made of the current object in a Category object named by the
          attribute directly under the root.

          The interface to the browsing database is through a file
          system implemented by jukefs.  The file system synthesises a
          directory per object.  Each directory contains a set of
          files describing the object's attributes:

               contains a new-line separated list of subobject names.
               For each name, x the directory /mnt/juke/x describes
               the subobject.

               contains a one-line summary of the object

               is a new-line separated list of file objects contained
               in this object.  Each line consists of object name and
               file name.

               is the fulltextual value of the object.

          key  contains the key by which objects are sorted

               is a one-line summary of the objects and the path lead-
               ing to it from the root.  This is the line displayed in
               the playlist and bottom browse windows of

               is the object reference to the parent of this object.


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     JUKE(7)                                                   JUKE(7)

               is a full description of the path leading to this
               object and the object itself.  This is the string dis-
               played in the top of the Browse and Playing windows of

          text is the text field of the object.

          type is the type of the object

          /sys/lib/music/map: Default map file /mnt/juke: Default
          mount point for the music database.



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