
Edith Manual            Filters          11th June 1994


FILTERS are currently only  an experimental feature  of
the editress package, and are not quite in  concordance
with  ZFC's  user-friendliness  guidelines.   This   is
subject to improvement in later versions.


(the rest of this page is highly advanced text)


A FILTER is a text based program (a TOS or TTP program)
called by Edith.   Up to 10  filters can be  installed;
they are activated by pressing ALTERNATE and a function
key  (from  inside  a  TEXT  WINDOW).   To  install   a
filter, select  a   function   key   in   the   FILTERS
dialog, and enter a name to  identify its use (this  is
not strictly necessary).  Then enter its full path name
in the  CMD  field.  Type  its  arguments in  the  ARGS
field.

   ** The EDITH system folder  has a subdirectory  BIN.
      For the  commands in  this directory,   the  full
      path   name   can   be   omitted.    In    future
      versions, Edith will  take  account of  the  PATH
      variable.

The  ARGUMENTS   can  contain   arbitrary   environment
variables, and the following special tokens:

   $IN      is expanded  to the  name of  a file  which
            contains the contents of the text selection
            when the filter was called.

   $OUT     is expanded  to the  name of  a file  where
            EDITH  expects  text  data  which  will  be
            substituted for  the text  selection  after
            termination of the filter

   $INOUT   is expanded to the  name of a file  serving
            for   passing   both   input   and   output
            selection.  Especially useful for calling a
            VT52 based text editor like VI or EMACS.

   $ENTER   when encountered causes an alert window  to
            be opened where the user can type a string.
            The string  is substituted  in the  command
            line.  Useful for e.g. BANNER.TTP


** More variables will be included in future  releases.
   Suggestions are welcome.


When SELECTION TO STANDARD OUTPUT is selected, the text
selection is sent to the keyboard input of the  filter.
When  SUBSTITUTE  STANDARD   OUTPUT  is   selected, the
terminal output of the  filter will be substituted  for
the selection.

When VT52  is selected, Edith  will try  to launch  the
program on a VT52 terminal.  Under plain single tasking
TOS, this means a white screen.  Under GEMINI with  the
EDITH accessory, this means the Mupfel console.   Under
MultiTOS, this means the console.



PROBLEMS

     Under MultiTOS,   the  console is  used  for  the
      VT-52 terminal.  See the printed manual for hints
      on how to automatically  launch a console  window
      when GEM is started.  It is a problem that typing
      into  the  console  window  is  a  bit  difficult
      (Gemini 1.99 has the same problem with the Mupfel
      console).

     GEMINI + accessory version:  the only combination
      that works is  Gemini 1.99  and a  non-redirected
      filter over the VT-52 terminal.

     EDITRESS.APP launched from Gemini:  filters  over
      a VT-52 terminal don't work.

We will attempt to solve these problems in the  future.
Expectedly,  Edith will have its own VT-52 window.



EXAMPLES

   cmd:  VI.TTP
   args: $INOUT
   over VT52.

   cmd:  MUPFEL.TTP
   over VT52

   cmd:  BANNER.TTP
   args: $ENTER
   substitute standard output

   cmd:  DATE.TTP
   substitute standard output

   cmd:  AWK.TTP
   args: d:\awkscript\$ENTER
   selection to standard input
   substitute standard output


Edith Manual            Filters          11th June 1994

