Add an operation into LAS

[Chi Ding <chi@xxxxxxxxx>]

Hi all ferret users
     I'm trying to add an operation into my LAS site. This operation is 
mapped onto
a matlab program and returns a gif file.
     As a first step, I added a new operation into las.xml file as below
<MooringPlotMatrix name="MooringPlotMatrix" class="LAS::Server::Ferret" 
method="MooringPlotMatrix"/>.  After that I called "make" to refresh the 
sql database.
     Then in the server/custom directory, I added a new function
sub MooringPlotMatrix {
   my $self = shift;
   my $props = $self->{props};

  $self->genImage("/home/local/las/server/output/logo.gif");  # 
Generate the image
}
  What I want to do is to return a gif file which is a constant file.
   However , when I call LASserver.pl using a valid XML request through
netscape,  I get an error like


adding an acceptable error string: "*** NOTE: ".
       NOAA/PMEL TMAP
       FERRET v5.53 
       Linux(g77) 2.4.x - 09/26/03
       28-Nov-03 12:54    
yes? cancel mode verify
yes? cancel mode interp
yes? canc data/all
yes? go std_initialize "/usr/local/ferret/go/mb1.nc" "1" "1" "wind_speed"
yes? go std_initialize "/usr/local/ferret/go/mb1.nc" "2" "1" 
"wind_direction"
yes? go std_initialize "/usr/local/ferret/go/mb1.nc" "3" "1" "sal_depth2"
yes? go std_initialize "/usr/local/ferret/go/mb1.nc" "4" "1" "temp_depth2"
yes? FRAME/FORMAT=gif/FILE="/home/local/las/server/output/logo.gif"
**ERROR: invalid command: No open workstations for batch FRAME command
  
   And I found the logo.gif was renamed to logo.gif.~1~

   Anybody can help me about this problem?
   Thanks a lot.
   Cheers, Ding