help with fsspecs vs. paramblocks

[duff@azrael.mitre.org (David A. Duff)]

i have what i hope is a simple question about how to access mac file
structures from lisp.

i'm using the quicktime example code (movie-window.lisp) that was made
available on cambridge.apple.com.  this code is working fine as is - but
i would now like to be able to specify (from a lisp pathname) the file
containing the quicktime movie to open.  currently, the example code
always invokes a standard file dialog to pick a file.

in picking apart the code, i've found that the #_OpenMovieFile trap
wants to be passed a structure of type :fsspec.  what i have is a lisp
pathname.  i've poked around in the examples and didn't find many places
where fsspec's were used.  i did find some interesting code in the file
ccl:examples:mac-file-io.lisp which defines FS-open.  looks like i'm
getting warm, but this function returns a paramblock (?! whatever that
is).  it appears from casual poking around that many of the traps
related to operations on files seem to work with paramblocks, yet the
quicktime trap for opening a movie wants an fsspec.  how do i get an
fsspec from a paramblock?

i'm hoping that this will be a trivial question for someone who's
programmed the mac in some language other than lisp.  i personally
haven't and i'm somewhat daunted by the idea of trying to borrow
someone's copy of Inside macintosh and getting completely lost in it...

thanks,

dave duff                   mitre corporation               703-883-7731
duff@mitre.org             ai technical center            mclean, va usa