rb_require_safe   421 include/ruby/intern.h VALUE rb_require_safe(VALUE, int);
rb_require_safe   821 load.c             return rb_require_safe(fname, rb_safe_level());
rb_require_safe   840 load.c             return rb_require_safe(rb_file_absolute_path(fname, base), rb_safe_level());
rb_require_safe  1057 load.c             return rb_require_safe(fn, rb_safe_level());
rb_require_safe   378 transcode.c            rb_require_safe(fn, safe > 3 ? 3 : safe);