Edith Manual          Filters       15th September 1994


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).


PRE-PACKED FILTERS

A number of useful  filters is automatically  installed
by INSTALL.PRG and can be used straight away:

   Alt F1   CALCULATOR
   
            Select a numeric expression (e.g. 30 + 40 *
            50) and hit Alt F1.  A window pops up  with
            the value of the expression.

   Alt F2   QUOTE

            Select a fragment of  text and hit Alt  F2.
            Every line is prefixed  with '> '. This  is
            especially useful for answering  electronic
            mail.

   Alt F3   COLUMN-BASED SORTING
   
            Select a fragment of text (e.g. statistical
            data, addresses, etc.), and move the cursor
            to the beginning of the COLUMN you wish  to
            sort the  data on.  (it doesn't  matter  on
            which line). Then hit Alt F3.

   Alt F4   REVERSE COLUMN-BASED SORTING
   
            Same,  but reverse-sorting is applied.

   Alt F5   NUMERIC COLUMN-BASED SORTING
   
            Again the same, but the data are sorted  on
            their value interpreted as double precision
            floating   point   numbers   rather    than
            alphabetically.

   Alt F6   TEXT INFO

            Provides  information  (bytes,  number   of
            words, etc.) about the selected text.

   Alt F7   SPELL

            Checks  your  spelling  according  to   the
            included   'rudimentary'   dictionary    of
            English, and  outputs  any words  which  it
            thinks are incorrect in a new window.

   Alt F8   REMOVE DUPLICATE LINES
   
            Removes duplicate  lines  in  the  selected
            text.



HOW TO INSTALL A FILTER

To install a filter, select the name of a function  key
in the FILTERS dialog, and enter a name to identify its
use (this is not strictly necessary). Then click on the
'CMD' field and select the filter in the file selector.
Type its arguments, if any, in the ARGS field.

These  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

   $SEL     The contents  of  the  first  line  in  the
            selection, literally.

   $TTSIZE  The true tab size of the text window

   $CURSCOL The current cursor  column when the  filter
            was called.



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 RUN FILTER OVER  TEXT TERMINAL 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.

When FILTER OUTPUT  TO NEW WINDOW  is selected, a  new,
read only,  window  will be  opened  the first  time  a
filter is called. From then on, all filter output  will
go into that window.


NOTES

   ù  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 2 has  the same problem  with the  Mupfel
      console).

   ù  Filters refuse  to work  when an  application  is
      started from Gemini  1.21. The accessory  version
      is always  OK.  Gemini  2.0  works  fine.  IT  IS
      NECESSARY that the command line caller  EDITH.TTP
      is in one of the directories in $PATH, for  Edith
      and the Gemini  console to properly  communicate.
      The command  line  caller  is used  to  tell  the
      Editress that the filter has terminated.


OTHER 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       15th September 1994