--- /dev/null
+// 2004-08-12 Paolo Carlini <pcarlini@suse.de>
+
+// Copyright (C) 2004, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+// 27.7.1.3 Overridden virtual functions
+
+#include <sstream>
+#include <testsuite_hooks.h>
+
+// libstdc++/16956
+void test01()
+{
+ bool test __attribute__((unused)) = true;
+ using namespace std;
+
+ typedef wstringbuf::int_type int_type;
+ typedef wstringbuf::traits_type traits_type;
+ typedef wstringbuf::pos_type pos_type;
+ typedef wstringbuf::off_type off_type;
+
+ wstringbuf strb_01(L"lara's place", ios_base::in);
+ pos_type pt_1 = strb_01.pubseekoff(5, ios_base::cur, ios_base::in);
+ int_type c1 = strb_01.sgetc();
+ VERIFY( c1 != traits_type::eof() );
+ pos_type pt_2 = strb_01.pubseekoff(2, ios_base::cur, ios_base::in);
+ pos_type pt_3 = strb_01.pubseekpos(pt_1, ios_base::in);
+ int_type c2 = strb_01.sbumpc();
+ VERIFY( off_type(pt_3) == off_type(pt_2) - 2 );
+ VERIFY( c2 == c1 );
+
+ wstringbuf strb_02(L"-", ios_base::out);
+ pos_type pt_4 = strb_02.pubseekoff(0, ios_base::cur, ios_base::out);
+ strb_02.sputn(L"red", 3);
+ pos_type pt_5 = strb_02.pubseekoff(-3, ios_base::cur, ios_base::out);
+ strb_02.pubseekpos(pt_5, ios_base::out);
+ VERIFY( off_type(pt_5) == off_type(pt_4) );
+ strb_02.sputn(L"blu", 3);
+ VERIFY( strb_02.str() == L"blu" );
+}
+
+int main()
+{
+ test01();
+ return 0;
+}