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//===----------------------------------------------------------------------===//
//
// ÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊThe LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <fstream>
// pos_type seekoff(off_type off, ios_base::seekdir way,
// ios_base::openmode which = ios_base::in | ios_base::out);
// pos_type seekpos(pos_type sp,
// ios_base::openmode which = ios_base::in | ios_base::out);
// This test is not entirely portable
#include <fstream>
#include <cassert>
template <class CharT>
struct test_buf
: public std::basic_filebuf<CharT>
{
typedef std::basic_filebuf<CharT> base;
typedef typename base::char_type char_type;
typedef typename base::int_type int_type;
typedef typename base::pos_type pos_type;
char_type* eback() const {return base::eback();}
char_type* gptr() const {return base::gptr();}
char_type* egptr() const {return base::egptr();}
void gbump(int n) {base::gbump(n);}
virtual int_type underflow() {return base::underflow();}
};
int main()
{
{
char buf[10];
typedef std::filebuf::pos_type pos_type;
std::filebuf f;
f.pubsetbuf(buf, sizeof(buf));
assert(f.open("seekoff.dat", std::ios_base::in | std::ios_base::out
| std::ios_base::trunc) != 0);
assert(f.is_open());
f.sputn("abcdefghijklmnopqrstuvwxyz", 26);
assert(buf[0] == 'v');
pos_type p = f.pubseekoff(-15, std::ios_base::cur);
assert(p == 11);
assert(f.sgetc() == 'l');
f.pubseekoff(0, std::ios_base::beg);
assert(f.sgetc() == 'a');
f.pubseekoff(-1, std::ios_base::end);
assert(f.sgetc() == 'z');
assert(f.pubseekpos(p) == p);
assert(f.sgetc() == 'l');
}
std::remove("seekoff.dat");
{
wchar_t buf[10];
typedef std::filebuf::pos_type pos_type;
std::wfilebuf f;
f.pubsetbuf(buf, sizeof(buf)/sizeof(buf[0]));
assert(f.open("seekoff.dat", std::ios_base::in | std::ios_base::out
| std::ios_base::trunc) != 0);
assert(f.is_open());
f.sputn(L"abcdefghijklmnopqrstuvwxyz", 26);
assert(buf[0] == L'v');
pos_type p = f.pubseekoff(-15, std::ios_base::cur);
assert(p == 11);
assert(f.sgetc() == L'l');
f.pubseekoff(0, std::ios_base::beg);
assert(f.sgetc() == L'a');
f.pubseekoff(-1, std::ios_base::end);
assert(f.sgetc() == L'z');
assert(f.pubseekpos(p) == p);
assert(f.sgetc() == L'l');
}
std::remove("seekoff.dat");
}
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