rb_reg_search0   1307 internal.h     long rb_reg_search0(VALUE, VALUE, long, int, int);
rb_reg_search0   1592 re.c               return rb_reg_search0(re, str, pos, reverse, 1);
rb_reg_search0   4510 string.c       	return rb_reg_search0(pat, str, pos, 0, set_backref_str);