basic_stringbuf::seekoff
The protected virtual member function tries to alter the current positions for the controlled streams.
virtual pos_type seekoff(
off_type _Off,
ios_base::seekdir _Way,
ios_base::openmode _Mode = ios_base::in | ios_base::out
);
Parameters
_Off
The position to seek for relative to _Way. For more information, see basic_stringbuf::off_type._Way
The starting point for offset operations. See ios_base::seekdir for possible values._Mode
Specifies the mode for the pointer position. The default is to allow you to modify the read and write positions. For more information, see ios_base::openmode.
Return Value
Returns the new position or an invalid stream position.
Remarks
For an object of class basic_stringbuf<Elem, Tr, Alloc>, a stream position consists purely of a stream offset. Offset zero designates the first element of the controlled sequence.
The new position is determined as follows:
If _Way == ios_base::beg, the new position is the beginning of the stream plus _Off.
If _Way == ios_base::cur, the new position is the current stream position plus _Off.
If _Way == ios_base::end, the new position is the end of the stream plus _Off.
If _Mode & ios_base::in is nonzero, the function alters the next position to read in the input buffer. If _Mode & ios_base::out is nonzero, the function alters the next position to write in the output buffer. For a stream to be affected, its buffer must exist. For a positioning operation to succeed, the resulting stream position must lie within the controlled sequence. If the function affects both stream positions, _Way must be ios_base::beg or ios_base::end and both streams are positioned at the same element. Otherwise (or if neither position is affected), the positioning operation fails.
If the function succeeds in altering either or both of the stream positions, it returns the resultant stream position. Otherwise, it fails and returns an invalid stream position.
Requirements
Header: <sstream>
Namespace: std