[MACTCL] Loading extensions under Tk on Macintosh

[Michael A. C. <mi...@cl...>]

I'm writing a multimedia Tk application which will be distributed on a
CD-ROM.  It uses the Snack extension for audio, and for video either
QuickTimeTcl/TMCI (Windows) or xanim drawing into a Tk frame (Linux;
probably eventually Solaris & *BSD too).

I'd like to add Macintosh support, but I'm having difficulty figuring out
how to (or if it's even possible) to load shared libraries off of the
CD-ROM on-the-fly.

The layout of the file system for the CD is:

    main.tcl
    assets/
    assets/audio
    assets/gifs
    assets/video
    lib/
    lib/generic
    lib/generic/BWidget-1.3.1
    lib/generic/MovieController
    lib/macintosh
    lib/macintosh/QuickTimeTcl
    lib/macintosh/snack2.1
    lib/linux
    lib/linux/Img1.2
    lib/linux/snack2.1
    lib/windows
    lib/windows/Img1.2
    lib/windows/QuickTimeTcl
    lib/windows/snack2.1
    lib/windows/tmci
    bin/
    tcl/

In the bin/ directory I have copies of the tclkit runtime for Windows &
Linux.  (To be clear, I'm not using/creating a scripted document; the
tclkit binaries are just a convenient way to get Tcl/Tk in one nice
self-contained package.)

The main.tcl script figures out where it's running from via [info script]
and then adds the following directories (using [file join]) to auto_path:

    $HOME/lib/[string tolower $tcl_platform(platform)]
    $HOME/lib/[string tolower $tcl_platform(os)]
    $HOME/lib/generic

This works like a charm for Windows & Linux.  Tcl is able to find the
right version of Snack & the other extensions.

On Macintosh, however, it doesn't seem to work--at least, not for the
compiled extensions (BWidgets doesn't have a problem).

I initially tried to use the static build of tclkit for the Macintosh and
the snack package wouldn't load snack.shlb.  I next downloaded the Tcl/Tk
8.3.4 binary from SF.  Same problem.

Only when I specifically installed the Snack .shlb's into the
"Applications:Tcl/Tk Folder 8.3.4:Tool Command Language" folder (and also
ran the QuickTimeTcl installer) was I able to load either package.

I only have limited experience with the Macintosh.  Can someone clue me in
on how I can have my app run on a Macintosh without making the end user
first install Tcl/Tk & then the extensions? Would it be possible to build
Tcl/Tk with QuickTimeTcl & Snack statically linked, and would this solve
my problem? (Not that I have a C compiler for the Mac, but I'd be happy to
PayPal someone who did.)  Or are my problems caused due to the fact that
the CD doesn't have data/resource fork info? And, without Tcl/Tk being
installed, could I work around this using the Mac-specific Tcl commands?

As you can see, I'm rather confused as to what to do.  :-)

Thanks in advance,

Michael