std::basic_streambuf<CharT,Traits>::pubseekoff, std::basic_streambuf<CharT,Traits>::seekoff
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std::basic_streambuf
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Positioning
basic_streambuf::pubseekoff
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Positioning
basic_streambuf::seekoff
Get area
Put area
Putback
pos_type pubseekoff( off_type off, std::ios_base::seekdir dir,
std::ios_base::openmode which = ios_base::in | ios_base::out );
(1)
std::ios_base::openmode which = ios_base::in | ios_base::out );
protected:
(2)
virtual pos_type seekoff( off_type off, std::ios_base::seekdir dir,
Sets the position indicator of the input and/or output sequence relative to some other position.
1) Calls seekoff(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:
which
-
defines which of the input and/or output sequences to affect. It can be one or a combination of the following constants:
repositions the file position, using relative addressing
(virtual protected member function of
repositions the next pointer in the input sequence, output sequence, or both, using relative addressing
(virtual protected member function of
Constant
Explanation
beg
the beginning of a stream
end
the ending of a stream
cur
the current position of stream position indicator
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 of seekoff for details.
[edit] Return value
1) The return value of seekoff(off, dir, which)
2) The resulting absolute position as defined by the position indicator. The base class version returns pos_type(off_type(-1)).
[edit] Example
This section is incomplete
Reason: no example
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 returnedan undefined invalid stream position |
returns pos_type(off_type(-1)) |
[edit] See also
[virtual]
(virtual protected member function of
std::basic_filebuf<CharT,Traits>) [edit]
[virtual]
(virtual protected member function of
std::basic_stringbuf<CharT,Traits,Allocator>) [edit]