Fabrizio,
> I managed to write some data into a file
> by:
> "
> with_stdout("./soluzione.cnf",
> for i : 1 thru length(solution) do
> print(solution[i])
> ),
> "
> after that I don't know whether the file
> is really closed but I adding after that
> "close("./soluzione.cnf")"
> does not help.
with_stdout closes the file automatically.
(with_stdout calls the Lisp function WITH-OPEN-FILE.)
> Then I read the file by:
> f: ?open(?"./soluzione.cnf"),
> and I close it by
> "close(f)",
There does not appear to be a Maxima function named close --
as Ray noted, you'll have to call ?close.
Also, ?"foo" does not make a Lisp string, but
sconcat returns a Lisp string -- you could write
f : ?open (sconcat ("./soluzione.cnf"));
(Some Lisp implementations accept a symbol in OPEN,
some don't.)
Hope this helps,
Robert