Can't run the simplest of programs. HELP

[Samohtvii]

I am simply trying to set-up my prolog environment and ii have a simply program.
write(a).
that's it...
It always tells me "No permission to modify static procedure `write/1'"
Also does the same for read. As i have never used prolog is it something wrong with how i have set it up or do i need something else to my code.

Thanks

 

[joel76]

You can't write write(a). in a Prolog program, you can type that in a Prolog console.
A Prolog program is made of facts and rules. When you write simply b] write(a).[/b] in a Prolog program, Prolog "thinks" that you assert a new fact write(a) so it doesn't want it.
You can write a rule

t :- write(a).