Member type char_type is the type of characters used by the stream (i.e., its first class template parameter, charT). sb A basic_streambuf object on whose controlled output sequence the characters are copied. If this is less than 2, the function does not extract any characters and sets failbit.ĭelim Explicit delimiting character: The operation of extracting successive characters stops as soon as the next character to extract compares equal to this (using traits_type::eq). N Maximum number of characters to write to s (including the terminating null character). If the function does not extract any characters (or if the first character extracted is the delimiter character) and n is greater than zero, this is set to an empty c-string. s Pointer to an array of characters where extracted characters are stored as a c-string. Parameters c The reference to a character where the extracted value is stored. The number of characters successfully read and stored by this function can be accessed by calling member gcount. Then (if good), it extracts characters from its associated stream buffer object as if calling its member functions sbumpc or sgetc, and finally destroys the sentry object before returning.
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Internally, the function accesses the input sequence by first constructing a sentry object (with noskipws set to true).
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If this is reached prematurely (before meeting the conditions described above), the function sets the eofbit flag. The function also stops extracting characters if the end-of-file is reached. Only the characters successfully inserted into sb are extracted from the stream: Neither the delimiting character, nor eventually the character that failed to be inserted at sb, are extracted from the input sequence and remain there as the next character to be extracted from the stream. (3) stream buffer Extracts characters from the stream and inserts them into the output sequence controlled by the stream buffer object sb, stopping either as soon as such an insertion fails or as soon as the delimiting character is encountered in the input sequence (the delimiting character being either the newline character or delim, if this argument is specified). The delimiting character is not extracted from the input sequence if found, and remains there as the next character to be extracted from the stream (see getline for an alternative that does discard the delimiting character).Ī null character ( char_type()) is automatically appended to the written sequence if n is greater than zero, even if an empty string is extracted. (2) c-string Extracts characters from the stream and stores them in s as a c-string, until either (n-1) characters have been extracted or the delimiting character is encountered: the delimiting character being either the newline character ( widen('\n')) or delim (if this argument is specified).
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The character is either returned (first signature), or set as the value of its argument (second signature). (1) single character Extracts a single character from the stream. Extracts characters from the stream, as unformatted input: