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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.
//
//===----------------------------------------------------------------------===//
// <fstream>
// template <class charT, class traits = char_traits<charT> >
// class basic_fstream
// template <class charT, class traits>
// void swap(basic_fstream<charT, traits>& x, basic_fstream<charT, traits>& y);
#include <fstream>
#include <utility>
#include <cassert>
#include "platform_support.h"
std::pair<std::string, std::string> get_temp_file_names() {
std::pair<std::string, std::string> names;
names.first = get_temp_file_name();
// Create the file so the next call to `get_temp_file_name()` doesn't
// return the same file.
std::FILE *fd1 = std::fopen(names.first.c_str(), "w");
names.second = get_temp_file_name();
assert(names.first != names.second);
std::fclose(fd1);
std::remove(names.first.c_str());
return names;
}
int main()
{
std::pair<std::string, std::string> temp_files = get_temp_file_names();
std::string& temp1 = temp_files.first;
std::string& temp2 = temp_files.second;
assert(temp1 != temp2);
{
std::fstream fs1(temp1.c_str(), std::ios_base::in | std::ios_base::out
| std::ios_base::trunc);
std::fstream fs2(temp2.c_str(), std::ios_base::in | std::ios_base::out
| std::ios_base::trunc);
fs1 << 1 << ' ' << 2;
fs2 << 2 << ' ' << 1;
fs1.seekg(0);
swap(fs1, fs2);
fs1.seekg(0);
int i;
fs1 >> i;
assert(i == 2);
fs1 >> i;
assert(i == 1);
i = 0;
fs2 >> i;
assert(i == 1);
fs2 >> i;
assert(i == 2);
}
std::remove(temp1.c_str());
std::remove(temp2.c_str());
{
std::wfstream fs1(temp1.c_str(), std::ios_base::in | std::ios_base::out
| std::ios_base::trunc);
std::wfstream fs2(temp2.c_str(), std::ios_base::in | std::ios_base::out
| std::ios_base::trunc);
fs1 << 1 << ' ' << 2;
fs2 << 2 << ' ' << 1;
fs1.seekg(0);
swap(fs1, fs2);
fs1.seekg(0);
int i;
fs1 >> i;
assert(i == 2);
fs1 >> i;
assert(i == 1);
i = 0;
fs2 >> i;
assert(i == 1);
fs2 >> i;
assert(i == 2);
}
std::remove(temp1.c_str());
std::remove(temp2.c_str());
}
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