JUKE(7) JUKE(7)
NAME
juke - music jukebox
SYNOPSIS
juke [ -t ] [ -w ] [ -h srvhost ] [ -s srvname ]
games/jukebox [ -t ] [ -w ]
games/jukefs [ -m mountpoint ] [ -s srvname ] [ mapfile ]
DESCRIPTION
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
script.
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.
Page 1 Plan 9 (printed 12/21/24)
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
/srv/jukefs.$user.
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)
performance{
Radio Filharmonisch Orkest Holland
Edo de Waart, conductor
recorded: Musikverein, Vienna, May 6, 1996
}
Page 2 Plan 9 (printed 12/21/24)
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.
Page 3 Plan 9 (printed 12/21/24)
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
file.
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:
children
contains a new-line separated list of subobject names.
For each name, x the directory /mnt/juke/x describes
the subobject.
digest
contains a one-line summary of the object
files
is a new-line separated list of file objects contained
in this object. Each line consists of object name and
file name.
fulltext
is the fulltextual value of the object.
key contains the key by which objects are sorted
miniparentage
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
games/jukebox.
parent
is the object reference to the parent of this object.
parentage
Page 4 Plan 9 (printed 12/21/24)
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
games/jukebox.
text is the text field of the object.
type is the type of the object
FILES
/sys/lib/music/map Default map file
/mnt/juke Default mount point for the music data-
base.
SOURCE
/sys/src/games/music
SEE ALSO
playlistfs(7), audio(7)
Page 5 Plan 9 (printed 12/21/24)