Success: [eclipse]: open(file1,update,s), writeln(s, X + 2), > writeln(s, Y + 3), close(s). X = _g90 Y = _g78 yes. [eclipse]: sh('cat file1'). _g90 + 2 _g78 + 3 yes. Error: writeln(S, a(b,c)). (Error 4). writeln("string", a(b,c)). (Error 5). writeln(9, X + 2). (Error 192). writeln(atom, X + 2). (Error 193).