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std::basic_filebuf(3)	      C++ Standard Libary	 std::basic_filebuf(3)

NAME
       std::basic_filebuf - std::basic_filebuf

Synopsis
	  Defined in header <fstream>
	  template<

	  class	CharT,
	  class	Traits = std::char_traits<CharT>

	  > class basic_filebuf	: public std::basic_streambuf<CharT, Traits>

	  std::basic_filebuf  is a std::basic_streambuf	whose associated char-
       acter sequence is
	  a file. Both the input sequence and the output sequence are  associ-
       ated with the same
	  file,	and a joint file position is maintained	for both operations.

	  The  functions  underflow() and overflow()/sync() perform the	actual
       I/O between the
	  file and the get and put areas of the	 buffer.  When	CharT  is  not
       char, most
	  implementations  store  multibyte  characters	 in  the  file	and  a
       std::codecvt facet is
	  used to perform wide/multibyte character conversion.

	  Two specializations for common character types are also defined:

	  Defined in header <streambuf>
	  Type	   Definition
	  filebuf  basic_filebuf<char>
	  wfilebuf basic_filebuf<wchar_t>

Member types
	  Member type Definition
	  char_type   CharT
	  traits_type Traits; the program is ill-formed	 if  Traits::char_type
       is not CharT.
	  int_type    Traits::int_type
	  pos_type	 Traits::pos_type    which    is    required   to   be
       std::fpos<Traits::state_type>
	  off_type    Traits::off_type

Member functions
Public member functions
	  constructor	constructs a basic_filebuf object
			(public	member function)
	  operator=	assigns	a basic_filebuf	object
	  (C++11)	(public	member function)
	  swap		swaps two basic_filebuf	objects
	  (C++11)	(public	member function)
	  destructor	destructs a basic_filebuf object and closes  the  file
       if it is	open
	  [virtual]	(virtual public	member function)
	  is_open	checks if the associated file is open
			(public	member function)
	  open		opens a	file and configures it as the associated char-
       acter sequence
			(public	member function)
	  close		 flushes the put area buffer and closes	the associated
       file
			(public	member function)

Protected member functions
	  showmanyc	optionally provides the	number of characters available
       for input from
	  [virtual]	the file
			(virtual protected member function)
	  underflow	reads from the associated file
	  [virtual]	(virtual protected member function)
	  uflow		reads from the associated file and advances  the  next
       pointer in the
	  [virtual]	get area
			(virtual protected member function)
	  pbackfail	backs out the input sequence to	unget a	character, not
       affecting the
	  [virtual]	associated file
			(virtual protected member function)
	  overflow	 writes	characters to the associated file from the put
       area
	  [virtual]	(virtual protected member function)
	  setbuf	provides user-supplied buffer or  turns	 this  filebuf
       unbuffered
	  [virtual]	(virtual protected member function)
	  seekoff	repositions the	file position, using relative address-
       ing
	  [virtual]	(virtual protected member function)
	  seekpos	repositions the	file position, using absolute address-
       ing
	  [virtual]	(virtual protected member function)
	  sync		 writes	characters to the associated file from the put
       area
	  [virtual]	(virtual protected member function)
	  imbue		changes	the associated locale
	  [virtual]	(virtual protected member function)

Non-member functions
	  std::swap(std::basic_filebuf)	specializes the	std::swap algorithm
	  (C++11)			(function template)

       Inherited from std::basic_streambuf

Member types
	  Member type Definition
	  char_type   CharT
	  traits_type Traits; the program is ill-formed	 if  Traits::char_type
       is not CharT.
	  int_type    Traits::int_type
	  pos_type    Traits::pos_type
	  off_type    Traits::off_type

Member functions
	  destructor	     destructs the basic_streambuf object
	  [virtual]	     (virtual public member function of
			     std::basic_streambuf<CharT,Traits>)

Locales
	  pubimbue	     invokes imbue()
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
	  getloc	     obtains a copy of the associated locale
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)

Positioning
	  pubsetbuf	     invokes setbuf()
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
	  pubseekoff	     invokes seekoff()
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
	  pubseekpos	     invokes seekpos()
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
	  pubsync	     invokes sync()
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)

Get area
			     obtains  the  number  of  characters  immediately
       available in the	get
	  in_avail	     area
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
			     advances the input	sequence, then reads one char-
       acter without
	  snextc	     advancing again
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
	  sbumpc	     reads one character from the input	 sequence  and
       advances	the
	  stossc	     sequence
	  (removed  in	C++17)	(public	 member	function of std::basic_stream-
       buf<CharT,Traits>)
			     reads one character from the input	sequence with-
       out advancing the
	  sgetc		     sequence
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
	  sgetn		     invokes xsgetn()
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)

Put area
			     writes one	character to the put area and advances
       the next
	  sputc		     pointer
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
	  sputn		     invokes xsputn()
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)

Putback
	  sputbackc	     puts one character	back in	the input sequence
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)
	  sungetc	     moves the next pointer in the input sequence back
       by one
			     (public  member  function	of  std::basic_stream-
       buf<CharT,Traits>)

Protected member functions
	  constructor	constructs a basic_streambuf object
			(protected member function)
	  operator=	replaces a basic_streambuf object
	  (C++11)	(protected member function)
	  swap		swaps two basic_streambuf objects
	  (C++11)	(protected member function)

Locales
	  imbue		changes	the associated locale
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)

Positioning
	  setbuf	replaces the buffer with user-defined array,  if  per-
       mitted
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
			repositions  the  next	pointer	in the input sequence,
       output sequence,
	  seekoff	or both, using relative	addressing
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
			repositions the	next pointer in	 the  input  sequence,
       output sequence,
	  seekpos	or both	using absolute addressing
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
	  sync		synchronizes the buffers with the associated character
       sequence
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)

Get area
			obtains	 the  number of	characters available for input
       in the associated
	  showmanyc	input sequence,	if known
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
	  underflow	reads characters from the associated input sequence to
       the get area
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
			reads characters from the associated input sequence to
       the get area
	  uflow		and advances the next pointer
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
	  xsgetn	reads multiple characters from the input sequence
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
	  eback		returns	a pointer to the beginning, current  character
       and the end of
	  gptr		the get	area
	  egptr		(protected member function)
	  gbump		advances the next pointer in the input sequence
			(protected member function)
			repositions  the  beginning, next, and end pointers of
       the input
	  setg		sequence
			(protected member function)

Put area
	  xsputn	writes multiple	characters to the output sequence
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
	  overflow	writes characters to the  associated  output  sequence
       from the	put area
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)
	  pbase		 returns a pointer to the beginning, current character
       and the end of
	  pptr		the put	area
	  epptr		(protected member function)
	  pbump		advances the next pointer of the output	sequence
			(protected member function)
			repositions the	beginning, next, and end  pointers  of
       the output
	  setp		sequence
			(protected member function)

Putback
			puts  a	character back into the	input sequence,	possi-
       bly modifying the
	  pbackfail	input sequence
	  [virtual]	(virtual protected member function of
			std::basic_streambuf<CharT,Traits>)

See also
	       object type, capable of holding all information needed to  con-
       trol a C	I/O
	  FILE stream
	       (typedef)

http://cppreference.com		  2022.07.31		 std::basic_filebuf(3)

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