> My question is whether I can insert a command that will appear in the
> header of an .html file created by LyX. I'd like to do it through the
> document settings or other means. Some background follows.
you can define your own script converting tex->html.
in preamble you will add some tex comment which does not change anything wrt
tex output but will be cought by your script. in case such comment is detected
you just pass the control to the previous script _and_ change the output file.
> I want to put some sort of security on the web versions to at least make it
> difficult to print the file. When I used OpenOffice, I could save a .pdf
> that required a password for printing.
don't see how to do directly inside lyx, but iirc pdftk utilities do this job,
so with some tweaking of your export scripts this could be automatized too.
>With LyX, I didn't see how to do
> this, but I inserted the lines:
>
> <style media="print">
>
> body {display: none;}
>
> </style>
imho these attempts to secure docs against printing are just waste of your time,
only very weak students dont find way how to put it in print.
pavel