Re: lynx-dev Passing internal data to external handlers

[pg]

In a recent note, Klaus Weide said:

> Date: Sun, 29 Nov 1998 06:14:40 -0600 (CST)
> 
> On Fri, 27 Nov 1998, Kim DeVaughn wrote:
> > Something that I like to do when I save documents, is to prepend a sort of
> > "header block" to them, telling from where and when they were obtained.  For
> 
> For the Title this is already being done: it should be passed in the
> environment variable LYNX_PRINT_TITLE to your script.  You might just
> expand that to set other variables for other things of interest.  That
> would certainly be simpler than defining a language with %tokens etc. for
> this purpose.
> 
I've pondered doing something similar.  In particular, I'd like Lynx to
invoke helper apps defined in .mailcap with the same environment variables
provided by metamail.  A brief exploration of the code led me to believe
that:

o The headers are traversed by a state machine which ignores what it
  isn't interested in; there's no simple way to capture the complete
  header text, which is one of the variables metamail places in the
  environment.

o The alternative of piping the document to metamail itself isn't
  easily achieved; again, Lynx discards the headers which metamail
  expects, and passes only the body to the application.

o Likewise "Lynx -source <URL> | metamail" discards the headers, and I
  see no easy way to preserve them.

o I haven't investigated EXTERNALS.  Is this a prospect for coupling
  Lynx to metamail for all unsupported document types?  Again, the headers
  would need to be preserved.

-- gil