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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <ostream>
// template <class charT, class traits = char_traits<charT> >
// class basic_ostream::sentry;
// explicit sentry(basic_ostream<charT,traits>& os);
#include <ostream>
#include <cassert>
int sync_called = 0;
template <class CharT>
struct testbuf1
: public std::basic_streambuf<CharT>
{
testbuf1() {}
protected:
int virtual sync()
{
++sync_called;
return 1;
}
};
int main()
{
{
std::ostream os((std::streambuf*)0);
std::ostream::sentry s(os);
assert(!bool(s));
}
{
testbuf1<char> sb;
std::ostream os(&sb);
std::ostream::sentry s(os);
assert(bool(s));
}
{
testbuf1<char> sb;
std::ostream os(&sb);
testbuf1<char> sb2;
std::ostream os2(&sb2);
os.tie(&os2);
assert(sync_called == 0);
std::ostream::sentry s(os);
assert(bool(s));
assert(sync_called == 1);
}
}
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