std::basic_streambuf<CharT,Traits>::pubseekoff,std::basic_streambuf<CharT,Traits>::seekoff

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Input/output library

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std::basic_streambuf

Public member functions
basic_streambuf::~basic_streambuf
Locales
basic_streambuf::pubimbue
basic_streambuf::getloc
Positioning
basic_streambuf::pubsetbuf
basic_streambuf::pubseekoff
basic_streambuf::pubseekpos
basic_streambuf::pubsync
Get area
basic_streambuf::in_avail
basic_streambuf::snextc
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basic_streambuf::sputn
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basic_streambuf::sungetc

Protected member functions
basic_streambuf::basic_streambuf
basic_streambuf::operator= (C++11)
basic_streambuf::swap (C++11)
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basic_streambuf::imbue
Positioning
basic_streambuf::setbuf
basic_streambuf::seekoff
basic_streambuf::seekpos
basic_streambuf::sync
Get area
basic_streambuf::showmanyc
basic_streambuf::underflow
basic_streambuf::uflow
basic_streambuf::xsgetn
basic_streambuf::ebackbasic_streambuf::gptrbasic_streambuf::egptr
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basic_streambuf::setg
Put area
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basic_streambuf::pbasebasic_streambuf::pptrbasic_streambuf::epptr
basic_streambuf::pbump
basic_streambuf::setp
Putback
basic_streambuf::pbackfail

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pos_type pubseekoff( off_type off,std::ios_base::seekdir dir, std::ios_base::openmode which= ios_base::in\| ios_base::out);	(1)
protected: virtual pos_type seekoff( off_type off,std::ios_base::seekdir dir, std::ios_base::openmode which= ios_base::in\| ios_base::out);	(2)

Sets the position indicator of the input and/or output sequence relative to some other position.

1) Callsseekoff(off, dir, which) of the most derived class.

2) The base class version of this function has no effect. The derived classes may override this function to allow relative positioning of the position indicator.

[edit]Parameters

off - relative position to set the position indicator to.

dir

defines base position to apply the relative offset to. It can be one of the following constants:

Constant	Explanation
`beg`	the beginning of a stream
`end`	the ending of a stream
`cur`	the current position of stream position indicator

which

defines which of the input and/or output sequences to affect. It can be one or a combination of the following constants:

Constant	Explanation
`in`	affect the input sequence
`out`	affect the output sequence

[edit]Note

Not all combinations of parameters may be valid, see the derived versions ofseekoff for details.

[edit]Return value

1) The return value ofseekoff(off, dir, which)

2) The resulting absolute position as defined by the position indicator. The base class version returnspos_type(off_type(-1)).

[edit]Example

This section is incomplete
Reason: no example

[edit]Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 55	C++98	the base class version of`seekoff` returned an undefined invalid stream position	returnspos_type(off_type(-1))

[edit]See also

pubseekpos	invokesseekpos() (public member function)[edit]
seekoff [virtual]	repositions the file position, using relative addressing (virtual protected member function of`std::basic_filebuf<CharT,Traits>`)[edit]
seekoff [virtual]	repositions the next pointer in the input sequence, output sequence, or both, using relative addressing (virtual protected member function of`std::basic_stringbuf<CharT,Traits,Allocator>`)[edit]
seekoff [virtual]	repositions the next pointer in the input sequence, output sequence, or both, using relative addressing (virtual protected member function of`std::strstreambuf`)[edit]