Modelsim Warning (vsim-PLI-3691)

Question

The following messages are displayed when I run simulation with modelsim 6.0.

Warning: (vsim-PLI-3691): Expected a system task, not a system function '$fseek'.
Warning: (vsim-PLI-3691): Expected a system task, not a system function '$sscanf'.

 

Is this a bug of Modelsim 6.0, or did I miss some files or setting?

Answer

$fseek as a task. It is a function, and returns a value. You must call it as a function.

In other words, you tried to do something like

begin
$fseek(fd,0,0);
end

begin
$sscanf(str,"%s_%d",name,no);
end

 

You must instead do something like

integer code;
begin
code = $fseek(fd,0,0);
end

integer ret;
begin
ret = $sscanf(str,"%s_%d",name,no);
end

 

Or actually use the return value as it was intended

begin
if ($fseek(fd,0,0) == -1)
    $display("ERROR: fseek failed");
end