return -1 from get_code to indicate end of file (#1622)

diff --git a/src/machine/system_calls.rs b/src/machine/system_calls.rs
index b154e266a591657356376cd515f72e343e719d78..f249f655e51e9647c54ef2f800bf279b0029ad4e 100644 (file)
--- a/src/machine/system_calls.rs
+++ b/src/machine/system_calls.rs
@@ -3058,11 +3058,10 @@ impl Machine {
         }
 
         if stream.at_end_of_stream() {
-            let end_of_file = atom!("end_of_file");
             stream.set_past_end_of_stream(true);
 
-            self.machine_st.unify_atom(
-                end_of_file,
+            self.machine_st.unify_fixnum(
+                Fixnum::build_with(-1),
                 self.machine_st.store(self.machine_st.deref(self.machine_st.registers[2])),
             );