bsl::basic_stringbuf::str

Return the currently buffered sequence of characters in a basic_string that uses the specified allocator. If this object was created only in input mode, the resultant basic_string contains the character sequence in the range [eback(), egptr())]. If modeBitMask & ios_base::out specified at construction is nonzero then the resultant basic_string contains the character sequence in the range [pbase(), high_mark)], where high_mark represents the position one past the highest initialized character in the buffer. Otherwise this object has been created in neither input nor output mode and a zero length basic_string is returned.