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mozplugger

NAME

mozplugger - a streaming multimedia plugin for UNIX mozilla

DESCRIPTION

MozPlugger is a Mozilla plugin which can show many types of multimedia inside your Mozilla. To accomplish this, MozPlugger uses external programs such as mplayer, xanim, mtv, timidity and tracker.

CONFIGURE FILE

You can configure mozplugger by changing the file mozpluggerrc which can be located in any of the following directories:

        $HOME/.netscape/

       $HOME/.mozilla/

       $HOME/.opera/

       $MOZILLA_HOME/

       $OPERA_HOME/

       /usr/local/netscape/

       /etc/

       /usr/local/mozilla/

       /usr/local/netscape/

The format of mozpluggerrc is very simple. The general layout is to have one or more lines describing mime types followed by one or more lines describing commands used to handle those mime types. Lines beginning with # are considered comments and are ignored. Here is a simple example:

        video/mpeg: mpeg: Mpeg video

       video/quicktime: qt,mov: Mpeg video

               : xanim +W$window -Zr +q +Ze +f $file

Each line describing a mime type has three fields:

        
mime type : extensions : description

mime type

The mime type is the standardized name for the content type you want MozPlugger to handle. This must be the same type as the web server claims the file to be, or MozPlugger will not be used for that file, regardless of the extension. Note: Some web servers incorrectly report the wrong mime type, blame the web server adminstrator not mozplugger.

extensions

This is a comma separated list of extensions that should be associated with this particular mime type. The extensions are only used when a web server does not report what type of file it is, or when loading files directly from disk.

description

This is the description that shows up in about:plugins and in the application preferences section in Mozilla.

Lines that describe what command to use for a mime type must begin

with a whitespace and have two fields:

        
flags : command

flags

This is a space separated list of flags which tells mozplugger how to handle this particular application. See below for further details.

command

This is a command which is sent to /bin/sh when handling this mime type.

USING M4

When loading, MozPlugger will pass the mozpluggerrc file through m4, a general purpose macro processor (assuming m4 is installed). This provides the ablity to use macros within mozpluggerrc especially for those commonly used command lines. m4 brings text replacement, parameter substitution, file inclusion, string manipulation, conditional evaluation, arthemtic expressions, etc to mozpluggerrc. Please see m4 documentation for more details.

FINDING THE RIGHT COMMAND

When MozPlugger is called from your browser, it looks through the configuration file and tries to find a matching mime type. For an application to be chosen it has to fulfill certain criteria, it has to exist, and it must match the flags given to mozplugger.

When it does, it tries to figure out which command to use. First, it looks through all the commands for that particular mime type to see if it can find an application that has the stream flag. If it cannot find a streaming application it downloads the file and tries again. Note that MozPlugger will check the first word of the command and search your $PATH for that command. If that command is not found MozPlugger will go to the next line in your mozpluggerrc.

WHEN IT DOESNT WORK

If for some reason the embedded object fails to be rendered in the browser, this could be a fault with the application as opposed to MozPlugger. To diagnosis the fault it is suggested that first you make sure that any output from the application will be visible to you by removing the noisy flag (if set in mozpluggerrc).

Next run the browser from the shell (xterm or equivalent) passing the appropriate browser command line flag to enable output from stdout and stderr to be displayed.

For example, for firefox the command line string is:

         firefox -debug

This should allow any output from the application to be visible at the shell and hopefully lead to a diagnosis of the fault.

FLAGS

repeat

This indicates that the command uses the $repeat variable.

loop

This indicates that the application loops forever. If the <EMBED> tag used to start MozPlugger indicated that the file should not loop forever, the command on this line will not be used.

stream

This indicates that this application can take an url. In this case, the variable $file contains the URL of the file to play and the browser does not download it.

ignore_errors

This flag tells MozPlugger to ignore the exit status of the application.

noisy

This flag tells MozPlugger to redirect the stdout and stderr of the application to /dev/null.

swallow (name)

It will tell mozplugger that the application will open a window with the specified name and that this window will then be moved to inside your browser. If name is prefixed with '=' then mozplugger looks for an exact match with the window name, if the prefix is '~' then mozplugger looks for a case insensitive match, if prefixed with '*' then mozplugger looks for a window name that starts with 'name' and is case insensitive. If none of these prefixes then, mozplugger checks if name occurs anywhere in the window name, but is case sensitive. Note any spaces between the brackets are counted as part of the window name. The window name to use in mozpluggerrc can be obtained by using the utility xprop(). Run the application in question, type "xprop WM_CLASS" at a shell prompt and then click on the application window.

fmatch (string)

This flag defines a command that will be used only if the filename or url (i.e. file) contains 'string'. If 'string' is prefixed with '*' then mozplugger defines a match when the file starts with 'string' (the check is case insensitive). If 'string' is prefixed with '%' then mozplugger defines a match when the file ends with 'string' (the check is case insenstive and ignores any parameters at the end of a url {i.e. '?xxx=yyy'}). If none of these prefixes then mozplugger defines a match when the 'string' is found somewhere in the file (but this time match is case sensitive). Note any spaces between the brackets are counted as part of the 'string'.

nokill

This tells MozPlugger to not try to kill the application when leaving the page, and to not start the application in a loop. This is normally used for applications that are not swallowed and can play multiple files, such as xmms.

fill

This keyword is used to maximize a swallowed window.

maxaspect

This keyword is used to maximize a swallowed window while keeping the width/height ratio constant.

controls

This flag is typically used with audio files to display a controller with the buttons play, pause and stop while playing.

embed, noembed

These flags can be used to define embed-only or full-window-only commands.

links

This flag is used for defining commands for embedded objects that are really links to external applications (such objects typically use the target and href variables to indicate a clickable link). Embedded Quicktime objects sometimes use this mechanism.

hidden

In conjunction with the swallow keyword, this tells the plugin to swallow windows which are not visible yet.

VARIABLES

MozPlugger gives some variables to /bin/sh when starting the application, these variables are:

$repeats

This variable contains how many times the file should be played. Applications which use this variable should also set the repeat flag.

$window

This is the X window Mozilla has given the plugin. This can be used with applications such as MPlayer to display graphics inside the mozilla window.

$width

This is the horizontal resolution in pixels.

$height

This is the vertical resolution in pixels.

$file

This is the file to play. If the application uses the stream flag, this this variable contains the URL of the file to play.

$mimetype

This variable contains the mime type of $file.

$VAR_<parameter_name>

All the parameters of the <EMBED> tags are made available in mozpluggerrc through environment variables. For example the parameter loop="1" in an <EMBED> tag defines the variable VAR_loop=1.

BUGS

You have to remove ~/.netscape/plugin-list or ~/.mozilla/firefox/pluginreg.dat after changing the configuration, or nothing will happen. This is a Netscape/Mozilla/Firefox bug, not a MozPlugger bug.

Netscape 3.x will not play anything for <EMBED> tags for which height or width are zero. This too is a Netscape bug.

Occassionally you may notice some zombie mozplugger-helper processes (defunct), this is not a bug, this is by design. The zombie processes occur when either the application exits or when using nokill flag (without exiting the page with the embedded object). The zombie(s) are reaped when closing the web page containing the associated embedded objects.

AUTHORS

Fredrik Hubinette, hubbe@hubbe.net
Louis Bavoil, louis@bavoil.net
Peter Leese, peter@leese.net