Index: ext/stringio/stringio.c
===================================================================
--- ext/stringio/stringio.c	(Revision 17351)
+++ ext/stringio/stringio.c	(Arbeitskopie)
@@ -992,7 +992,7 @@
     VALUE *argv;
     VALUE self;
 {
-    VALUE line = strio_getline(argc, argv, readable(StringIO(self)));
+    VALUE line = strio_gets(argc, argv, self);
     if (NIL_P(line)) rb_eof_error();
     return line;
 }