STD::FILEBUF(3)

🌸 std::basic_filebuf< _CharT, _Traits > 💖

okay bestie, welcome to the Library Functions Manual, section 3 — this is the std::basic_filebuf< _CharT, _Traits > page and it's literally the main character of file I/O in C++. grab a snack, we're doing this. 🍓

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✨ NAME ✨

std::basic_filebuf< _CharT, _Traits > — the actual work of input and output (for files). yeah. she does the real labor. no cap. 💅

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🦋 SYNOPSIS 🦋

#include <fstream>

Inherits std::basic_streambuf< _CharT, _Traits >.

Inherited by __gnu_cxx::stdio_filebuf< _CharT, _Traits >.

👑 Public Types

• typedef codecvt< char_type, char, __state_type > __codecvt_type
• typedef __basic_file< char > __file_type
• typedef basic_filebuf< char_type, traits_type > __filebuf_type
• typedef traits_type::state_type __state_type
• typedef basic_streambuf< char_type, traits_type > __streambuf_type
• typedef _CharT char_type
• typedef traits_type::int_type int_type
• typedef traits_type::off_type off_type
• typedef traits_type::pos_type pos_type
• typedef _Traits traits_type

💖 Public Member Functions

• basic_filebuf () — Does not open any files.
• basic_filebuf (basic_filebuf &&)
• basic_filebuf (const basic_filebuf &)=delete
• virtual ~basic_filebuf () — The destructor closes the file first.
• __filebuf_type * close () — Closes the currently associated file.
• locale getloc () const — Locale access.
• streamsize in_avail () — Looking ahead into the stream.
• bool is_open () const throw () — Returns true if the external file is open.
• template<typename _Path> _If_fs_path< _Path, __filebuf_type * > open (const _Path &__s, ios_base::openmode __mode) — Opens an external file.
• __filebuf_type * open (const char *__s, ios_base::openmode __mode) — Opens an external file.
• __filebuf_type * open (const std::string &__s, ios_base::openmode __mode) — Opens an external file.
• basic_filebuf & operator= (basic_filebuf &&)
• basic_filebuf & operator= (const basic_filebuf &)=delete
• locale pubimbue (const locale &__loc) — Entry point for imbue().
• int_type sbumpc () — Getting the next character.
• int_type sgetc () — Getting the next character.
• streamsize sgetn (char_type *__s, streamsize __n) — Entry point for xsgetn.
• int_type snextc () — Getting the next character.
• int_type sputbackc (char_type __c) — Pushing characters back into the input stream.
• int_type sputc (char_type __c) — Entry point for all single-character output functions.
• streamsize sputn (const char_type *__s, streamsize __n) — Entry point for all single-character output functions.
• int_type sungetc () — Moving backwards in the input stream.
• void swap (basic_filebuf &)
  • basic_streambuf * pubsetbuf (char_type *__s, streamsize __n) — Entry points for derived buffer functions.
  • pos_type pubseekoff (off_type __off, ios_base::seekdir __way, ios_base::openmode __mode=ios_base::in|ios_base::out) — Alters the stream position.
  • pos_type pubseekpos (pos_type __sp, ios_base::openmode __mode=ios_base::in|ios_base::out) — Alters the stream position.
  • int pubsync () — Calls virtual sync function.

🎀 Protected Member Functions

• void __safe_gbump (streamsize __n)
• void __safe_pbump (streamsize __n)
• void _M_allocate_internal_buffer ()
• bool _M_convert_to_external (char_type *, streamsize)
• void _M_create_pback ()
• void _M_destroy_internal_buffer () throw ()
• void _M_destroy_pback () throw ()
• int _M_get_ext_pos (__state_type &__state)
• pos_type _M_seek (off_type __off, ios_base::seekdir __way, __state_type __state)
• void _M_set_buffer (streamsize __off)
• bool _M_terminate_output ()
• void gbump (int __n) — Moving the read position.
• virtual void imbue (const locale &__loc) — Changes translations.
• virtual int_type overflow (int_type __c=_Traits::eof()) — Consumes data from the buffer; writes to the controlled sequence.
• virtual int_type pbackfail (int_type __c=_Traits::eof()) — Tries to back up the input sequence.
• void pbump (int __n) — Moving the write position.
• virtual pos_type seekoff (off_type __off, ios_base::seekdir __way, ios_base::openmode __mode=ios_base::in|ios_base::out) — Alters the stream positions.
• virtual pos_type seekpos (pos_type __pos, ios_base::openmode __mode=ios_base::in|ios_base::out) — Alters the stream positions.
• virtual __streambuf_type * setbuf (char_type *__s, streamsize __n) — Manipulates the buffer.
• void setg (char_type *__gbeg, char_type *__gnext, char_type *__gend) — Setting the three read area pointers.
• void setp (char_type *__pbeg, char_type *__pend) — Setting the three write area pointers.
• virtual streamsize showmanyc () — Investigating the data available.
• void swap (basic_streambuf &__sb)
• virtual int sync () — Synchronizes the buffer arrays with the controlled sequences.
• virtual int_type uflow () — Fetches more data from the controlled sequence.
• virtual int_type underflow () — Fetches more data from the controlled sequence.
• virtual streamsize xsgetn (char_type *__s, streamsize __n) — Multiple character extraction.
• virtual streamsize xsputn (const char_type *__s, streamsize __n) — Multiple character insertion.
  • char_type * eback () const — Access to the get area.
  • char_type * gptr () const — Access to the get area.
  • char_type * egptr () const — Access to the get area.
  • char_type * pbase () const — Access to the put area.
  • char_type * pptr () const — Access to the put area.
  • char_type * epptr () const — Access to the put area.

🌈 Protected Attributes

• char_type * _M_buf — Pointer to the beginning of internal buffer.
• bool _M_buf_allocated
• locale _M_buf_locale — Current locale setting.
• size_t _M_buf_size
• const __codecvt_type * _M_codecvt
• char * _M_ext_buf
• streamsize _M_ext_buf_size
• char * _M_ext_end
• const char * _M_ext_next
• __file_type _M_file
• char_type * _M_in_beg — Start of get area.
• char_type * _M_in_cur — Current read area.
• char_type * _M_in_end — End of get area.
• __c_lock _M_lock
• ios_base::openmode _M_mode — Place to stash in || out || in | out settings for current filebuf.
• char_type * _M_out_beg — Start of put area.
• char_type * _M_out_cur — Current put area.
• char_type * _M_out_end — End of put area.
• bool _M_reading
• __state_type _M_state_beg
• __state_type _M_state_cur
• __state_type _M_state_last
• bool _M_writing
  • char_type _M_pback
  • char_type * _M_pback_cur_save
  • char_type * _M_pback_end_save
  • bool _M_pback_init

🫶 Friends

• class ios_base

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💜 Detailed Description 💜

template<typename _CharT, typename _Traits>
    class std::basic_filebuf< _CharT, _Traits >

"The actual work of input and output (for files)." like, that's the whole personality. 💅

🌟 Template Parameters

• _CharT — Type of character stream.
• _Traits — Traits for character type, defaults to char_traits<_CharT>.

This class associates both its input and output sequence with an external disk file, and maintains a joint file position for both sequences. Many of its semantics are described in terms of similar behavior in the Standard C Library's FILE streams. (yes bestie, she's giving FILE energy but make it ✨templated✨)

Requirements on traits_type, specific to this class:

• traits_type::pos_type must be fpos<traits_type::state_type>
• traits_type::off_type must be streamoff
• traits_type::state_type must be Assignable and DefaultConstructible,
• traits_type::state_type() must be the initial state for codecvt.

fr fr these are non-negotiable. the vibes are strict here. 🔥

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🧚 Constructor & Destructor Documentation 🧚

template<typename _CharT, typename _Traits> std::basic_filebuf< _CharT, _Traits >::basic_filebuf ()

Does not open any files. The default constructor initializes the parent class using its own default ctor.

References _M_buf, std::basic_streambuf< _CharT, _Traits >::_M_buf_locale, _M_buf_size, _M_ext_buf, _M_ext_buf_size, _M_ext_next, _M_mode, _M_pback, _M_pback_cur_save, _M_pback_end_save, _M_pback_init, and _M_reading.

Referenced by __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), and close().

template<typename _CharT, typename _Traits> virtual std::basic_filebuf< _CharT, _Traits >::~basic_filebuf () [inline], [virtual]

The destructor closes the file first. she cleans up after herself, periodt. 🎀

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⭐ Member Function Documentation ⭐

template<typename _CharT, typename _Traits> void std::basic_filebuf< _CharT, _Traits >::_M_create_pback () [inline], [protected]

Initializes pback buffers, and moves normal buffers to safety. Assumptions: _M_in_cur has already been moved back

Referenced by pbackfail().

template<typename _CharT, typename _Traits> void std::basic_filebuf< _CharT, _Traits >::_M_destroy_pback () [inline], [protected]

Deactivates pback buffer contents, and restores normal buffer. Assumptions: The pback buffer has only moved forward.

Referenced by overflow(), seekoff(), seekpos(), underflow(), and xsgetn().

template<typename _CharT, typename _Traits> void std::basic_filebuf< _CharT, _Traits >::_M_set_buffer (streamsize __off) [inline], [protected]

This function sets the pointers of the internal buffer, both get and put areas. Typically:

__off == egptr() - eback() upon underflow/uflow (read mode); __off == 0 upon overflow (write mode); __off == -1 upon open, setbuf, seekoff/pos (uncommitted mode).

NB: epptr() - pbase() == _M_buf_size - 1, since _M_buf_size reflects the actual allocated memory and the last cell is reserved for the overflow char of a full put area.

Referenced by __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), close(), imbue(), open(), overflow(), pbackfail(), underflow(), xsgetn(), and xsputn().

template<typename _CharT, typename _Traits> basic_filebuf< _CharT, _Traits >::__filebuf_type * std::basic_filebuf< _CharT, _Traits >::close ()

Closes the currently associated file.

Returns this on success, NULL on failure

If no file is currently open, this function immediately fails.

If a put buffer area exists, overflow(eof) is called to flush all the characters. The file is then closed.

If any operations fail, this function also fails.

References basic_filebuf(), _M_mode, _M_pback_init, _M_reading, _M_set_buffer(), and is_open().

Referenced by std::basic_filebuf< char_type, traits_type >::~basic_filebuf(), and open().

template<typename _CharT, typename _Traits> char_type * std::basic_streambuf< _CharT, _Traits >::eback () const [inline], [protected], [inherited]

Access to the get area. These functions are only available to other protected functions, including derived classes. 🔒

• eback() returns the beginning pointer for the input sequence
• gptr() returns the next pointer for the input sequence
• egptr() returns the end pointer for the input sequence

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to be continued, bestie… 🌸

And this one’s “Referenced by” list is giving main character energy — literally everyone wants a piece 💅

• std::basic_filebuf< char_type, traits_type >::_M_destroy_pback()
• std::basic_filebuf< _CharT, _Traits >::imbue()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow()
• std::basic_filebuf< _CharT, _Traits >::pbackfail()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::pbackfail()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos()
• std::basic_streambuf< char_type, traits_type >::sputbackc()
• std::basic_streambuf< char_type, traits_type >::sungetc()
• std::basic_filebuf< _CharT, _Traits >::underflow()
• and std::basic_filebuf< _CharT, _Traits >::xsgetn()

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✨ egptr() — the get area’s end pointer ✨

template<typename _CharT, typename _Traits> char_type *
    std::basic_streambuf< _CharT, _Traits >::egptr () const [inline],
    [protected],  [inherited]

Okay so this is your access to the get area situation, bestie. These functions are only available to other protected functions, including derived classes. No cap.

• eback() returns the beginning pointer for the input sequence
• gptr() returns the next pointer for the input sequence
• egptr() returns the end pointer for the input sequence

Referenced by everyone and their mom:

• std::basic_filebuf< char_type, traits_type >::_M_create_pback()
• std::basic_streambuf< char_type, traits_type >::in_avail()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow()
• std::basic_streambuf< char_type, traits_type >::sbumpc()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos()
• std::basic_streambuf< char_type, traits_type >::sgetc()
• std::basic_filebuf< _CharT, _Traits >::showmanyc()
• std::basic_stringbuf< char >::showmanyc()
• std::basic_filebuf< _CharT, _Traits >::underflow()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::underflow()
• std::wbuffer_convert< _Codecvt, _Elem, _Tr >::underflow()
• std::basic_filebuf< _CharT, _Traits >::xsgetn()
• and xsgetn()

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🦋 epptr() — the put area’s end pointer 🦋

template<typename _CharT, typename _Traits> char_type *
    std::basic_streambuf< _CharT, _Traits >::epptr () const [inline],
    [protected],  [inherited]

Access to the put area, periodt. These functions are only available to other protected functions, including derived classes. iykyk 💜

• pbase() returns the beginning pointer for the output sequence
• pptr() returns the next pointer for the output sequence
• epptr() returns the end pointer for the output sequence

Referenced by:

• std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos()
• std::basic_streambuf< char_type, traits_type >::sputc()
• std::basic_filebuf< _CharT, _Traits >::xsputn()
• and xsputn()

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💅 gbump() — moving the read position 💅

template<typename _CharT, typename _Traits> void std::basic_streambuf<
    _CharT, _Traits >::gbump (int __n) [inline],  [protected],  [inherited]

Moving the read position. Lowkey simple, highkey useful.

Parameters

• __n — The delta by which to move.

This just advances the read position without returning any data. Not me being like “move, bestie, move” and giving you zero characters back 😭

Referenced by:

• std::basic_filebuf< _CharT, _Traits >::pbackfail()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::pbackfail()
• std::basic_streambuf< char_type, traits_type >::sbumpc()
• std::basic_streambuf< char_type, traits_type >::sputbackc()
• std::basic_streambuf< char_type, traits_type >::sungetc()
• std::basic_streambuf< char_type, traits_type >::uflow()
• and std::basic_filebuf< _CharT, _Traits >::xsgetn()

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🌸 getloc() — locale access 🌸

template<typename _CharT, typename _Traits> locale std::basic_streambuf<
    _CharT, _Traits >::getloc () const [inline],  [inherited]

Locale access. It’s giving “who’s in charge of the vibe right now?” ✨

Returns

• The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Referenced by std::basic_streambuf< char_type, traits_type >::pubimbue().

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🎀 gptr() — the get area’s next pointer 🎀

template<typename _CharT, typename _Traits> char_type *
    std::basic_streambuf< _CharT, _Traits >::gptr () const [inline],
    [protected],  [inherited]

Access to the get area. These functions are only available to other protected functions, including derived classes. Protected bestie behavior, fr fr.

• eback() returns the beginning pointer for the input sequence
• gptr() returns the next pointer for the input sequence
• egptr() returns the end pointer for the input sequence

Referenced by the whole friend group:

• std::basic_filebuf< char_type, traits_type >::_M_create_pback()
• std::basic_filebuf< char_type, traits_type >::_M_destroy_pback()
• std::basic_filebuf< _CharT, _Traits >::imbue()
• std::basic_streambuf< char_type, traits_type >::in_avail()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow()
• std::basic_filebuf< _CharT, _Traits >::pbackfail()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::pbackfail()
• std::basic_streambuf< char_type, traits_type >::sbumpc()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff()
• std::basic_streambuf< char_type, traits_type >::sgetc()
• std::basic_filebuf< _CharT, _Traits >::showmanyc()
• std::basic_stringbuf< char >::showmanyc()
• std::basic_streambuf< char_type, traits_type >::sputbackc()
• std::basic_streambuf< char_type, traits_type >::sungetc()
• std::basic_streambuf< char_type, traits_type >::uflow()
• std::basic_filebuf< _CharT, _Traits >::underflow()
• std::basic_stringbuf< _CharT, _Traits, _Alloc >::underflow()
• std::wbuffer_convert< _Codecvt, _Elem, _Tr >::underflow()
• std::basic_filebuf< _CharT, _Traits >::xsgetn()
• and xsgetn()

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🌈 imbue() — changes translations 🌈

template<typename _CharT, typename _Traits> void std::basic_filebuf< _CharT,
    _Traits >::imbue (const locale & __loc) [protected],  [virtual]

Changes translations. Glow-up for your I/O locale. 💖

Parameters

• __loc — A new locale.

Translations done during I/O which depend on the current locale are changed by this call. The standard adds, Between invocations of this function a class derived from streambuf can safely cache results of calls to locale functions and to members of facets so obtained.

Note — Base class version does nothing.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References:

• _M_ext_buf
• _M_ext_next
• _M_mode
• _M_reading
• _M_set_buffer()
• std::ios_base::cur
• std::basic_streambuf< _CharT, _Traits >::eback()
• std::basic_streambuf< _CharT, _Traits >::gptr()
• is_open()
• and seekoff()

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⭐ in_avail() — looking ahead into the stream ⭐

template<typename _CharT, typename _Traits> streamsize std::basic_streambuf<
    _CharT, _Traits >::in_avail () [inline],  [inherited]

Looking ahead into the stream. Spoiler alert, but make it buffered. 👑

Returns

• The number of characters available.

If a read position is available, returns the number of characters available for reading before the buffer must be refilled. Otherwise returns the derived showmanyc().

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🫶 is_open() — is the external file open? 🫶

template<typename _CharT, typename _Traits> bool std::basic_filebuf< _CharT,
    _Traits >::is_open () const [inline],  [nodiscard]

Returns true if the external file is open. Simple. Iconic. No notes. ✅

Referenced by:

• __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf()
• __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf()
• close()
• imbue()
• open()
• seekoff()
• seekpos()
• setbuf()
• and showmanyc()

---

✨ open() — the filesystem::path version ✨

template<typename _CharT, typename _Traits> template<typename _Path>
    _If_fs_path< _Path, __filebuf_type * > std::basic_filebuf< _CharT,
    _Traits >::open (const _Path & __s, ios_base::openmode __mode) [inline]

Opens an external file. Path girlies, this one’s for you. 💅

Parameters

• __s — The name of the file, as a filesystem::path.
• __mode — The open mode flags.

Returns

• this on success, NULL on failure

---

🔥 open() — the const char * version 🔥

template<typename _CharT, typename _Traits> basic_filebuf< _CharT, _Traits
    >::__filebuf_type * std::basic_filebuf< _CharT, _Traits >::open (const
    char * __s, ios_base::openmode __mode)

Opens an external file. The classic char-pointer entrance. ✨

Parameters

• __s — The name of the file.
• __mode — The open mode flags.

Returns

• this on success, NULL on failure

If a file is already open, this function immediately fails. Otherwise it tries to open the file named __s using the flags given in __mode.

Table 92, adapted here, gives the relation between openmode combinations and the equivalent fopen() flags. (NB: lines app, in|out|app, in|app, binary|app, binary|in|out|app, and binary|in|app per DR 596)

• binary off, in off, out on, trunc off, app off → w
• binary off, in off, out on, trunc off, app on → a
• binary off, in off, out off, trunc off, app on → a
• binary off, in off, out on, trunc on, app off → w
• binary off, in on, out off, trunc off, app off → r
• binary off, in on, out on, trunc off, app off → r+
• binary off, in on, out on, trunc on, app off → w+
• binary off, in on, out on, trunc off, app on → a+
• binary off, in on, out off, trunc off, app on → a+
• binary on, in off, out on, trunc off, app off → wb
• binary on, in off, out on, trunc off, app on → ab
• binary on, in off, out off, trunc off, app on → ab
• binary on, in off, out on, trunc on, app off → wb
• binary on, in on, out off, trunc off, app off → rb
• binary on, in on, out on, trunc off, app off → r+b
• binary on, in on, out on, trunc on, app off → w+b
• binary on, in on, out on, trunc off, app on → a+b
• binary on, in on, out off, trunc off, app on → a+b

References:

• _M_mode
• _M_reading
• _M_set_buffer()
• std::ios_base::ate
• close()
• std::ios_base::end
• is_open()
• and seekoff()

Referenced by:

• std::basic_filebuf< char_type, traits_type >::open()
• and std::basic_filebuf< char_type, traits_type >::open()

---

💜 open() — the std::string version 💜

template<typename _CharT, typename _Traits> __filebuf_type *
    std::basic_filebuf< _CharT, _Traits >::open (const std::string & __s,
    ios_base::openmode __mode) [inline]

Opens an external file. String besties, we see you. 🎀

Parameters

• __s — The name of the file.
• __mode — The open mode flags.

Returns

• this on success, NULL on failure

---

🌈 overflow() — consumes data from the buffer; writes to the controlled sequence 🌈

template<typename _CharT, typename _Traits> basic_filebuf< _CharT, _Traits
    >::int_type std::basic_filebuf< _CharT, _Traits >::overflow (int_type
    __c = _Traits::eof()) [protected],  [virtual]

Consumes data from the buffer; writes to the controlled sequence. It’s giving “the buffer said I’m full, but make it fashion.” 💀

Parameters

• __c — An additional character to consume.

Returns

• eof() to indicate failure, something else (usually __c, or not_eof())

Informally, this one gets called when the output buffer is full (or doesn't even exist, bc buffering doesn't actually have to happen). If a buffer does exist, it gets consumed, with some effect on the controlled sequence — typically the buffer is written out to the sequence verbatim. Either way, the character c is also written out, as long as __c is not eof().

For the formal definition of this function, go read a good text like Langer & Kreft, or [27.5.2.4.5]/3-7.

Bestie hack: you can make a functioning output streambuf by overriding only this one function (no buffer area will be used at all ✨).

Note: the base class version does literally nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References _M_buf_size, _M_destroy_pback(), _M_mode, _M_reading, _M_set_buffer(), std::ios_base::app, std::ios_base::cur, std::ios_base::out, std::basic_streambuf< _CharT, _Traits >::pbase(), std::basic_streambuf< _CharT, _Traits >::pbump(), and std::basic_streambuf< _CharT, _Traits >::pptr().

Referenced by pbackfail(), sync(), underflow(), and xsgetn().

---

🦋 template<typename _CharT, typename _Traits> basic_filebuf< _CharT, _Traits >::int_type std::basic_filebuf< _CharT, _Traits >::pbackfail (int_type __c = _Traits::eof()) [protected], [virtual]

Tries to back up the input sequence. (Yes, like walking backwards through a hallway you already slayed 💅)

Parameters

• __c — The character to be inserted back into the sequence.

Returns

• eof() on failure, some other value on success.

Postcondition

• The constraints of gptr(), eback(), and pptr() are the same as for underflow().

Note: the base class version does nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References _M_create_pback(), _M_mode, _M_pback_init, _M_reading, _M_set_buffer(), std::ios_base::cur, std::basic_streambuf< _CharT, _Traits >::eback(), std::basic_streambuf< _CharT, _Traits >::gbump(), std::basic_streambuf< _CharT, _Traits >::gptr(), std::ios_base::in, overflow(), seekoff(), and underflow().

---

💖 template<typename _CharT, typename _Traits> char_type * std::basic_streambuf< _CharT, _Traits >::pbase () const [inline], [protected], [inherited]

Access to the put area. These functions are only available to other protected functions, including derived classes. (It's giving VIP-only, iykyk 🎀)

• pbase() returns the beginning pointer for the output sequence
• pptr() returns the next pointer for the output sequence
• epptr() returns the end pointer for the output sequence

Referenced by std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_filebuf< _CharT, _Traits >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), std::basic_stringbuf< char >::str(), std::basic_filebuf< _CharT, _Traits >::sync(), and std::basic_filebuf< _CharT, _Traits >::xsputn().

---

✨ template<typename _CharT, typename _Traits> void std::basic_streambuf< _CharT, _Traits >::pbump (int __n) [inline], [protected], [inherited]

Moving the write position. Periodt.

Parameters

• __n — The delta by which to move.

This just advances the write position without returning any data.

Referenced by std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), and std::basic_streambuf< char_type, traits_type >::sputc().

---

🫶 template<typename _CharT, typename _Traits> char_type * std::basic_streambuf< _CharT, _Traits >::pptr () const [inline], [protected], [inherited]

Access to the put area. These functions are only available to other protected functions, including derived classes. (Again: protected-only, no gatekeeping complaints allowed 🌸)

• pbase() returns the beginning pointer for the output sequence
• pptr() returns the next pointer for the output sequence
• epptr() returns the end pointer for the output sequence

Referenced by std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_filebuf< _CharT, _Traits >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_streambuf< char_type, traits_type >::sputc(), std::basic_filebuf< _CharT, _Traits >::sync(), std::basic_filebuf< _CharT, _Traits >::xsputn(), and xsputn().

---

🌈 template<typename _CharT, typename _Traits> locale std::basic_streambuf< _CharT, _Traits >::pubimbue (const locale & __loc) [inline], [inherited]

Entry point for imbue().

Parameters

• __loc — The new locale.

Returns

• The previous locale.

Calls the derived imbue(__loc).

---

🦋 template<typename _CharT, typename _Traits> pos_type std::basic_streambuf< _CharT, _Traits >::pubseekoff (off_type __off, ios_base::seekdir __way, ios_base::openmode __mode = ios_base::in | ios_base::out) [inline], [inherited]

Alters the stream position.

Parameters

• __off — Offset.
• __way — Value for ios_base::seekdir.
• __mode — Value for ios_base::openmode.

Calls virtual seekoff function.

---

💅 template<typename _CharT, typename _Traits> pos_type std::basic_streambuf< _CharT, _Traits >::pubseekpos (pos_type __sp, ios_base::openmode __mode = ios_base::in | ios_base::out) [inline], [inherited]

Alters the stream position.

Parameters

• __sp — Position
• __mode — Value for ios_base::openmode.

Calls virtual seekpos function.

---

🍓 template<typename _CharT, typename _Traits> basic_streambuf * std::basic_streambuf< _CharT, _Traits >::pubsetbuf (char_type * __s, streamsize __n) [inline], [inherited]

Entry points for derived buffer functions. The public versions of pubfoo dispatch to the protected derived foo member functions, passing the arguments (if any) and returning the result unchanged. (The pub ones are literally just the friendly front desk, the real work happens in the protected foo behind the scenes 👑)

---

💜 template<typename _CharT, typename _Traits> int std::basic_streambuf< _CharT, _Traits >::pubsync () [inline], [inherited]

Calls virtual sync function.

Referenced by std::basic_istream< _CharT, _Traits >::sync().

---

🎀 template<typename _CharT, typename _Traits> int_type std::basic_streambuf< _CharT, _Traits >::sbumpc () [inline], [inherited]

Getting the next character.

Returns

• The next character, or eof.

If the input read position is available, returns that character and increments the read pointer, otherwise calls and returns uflow().

Referenced by std::basic_istream< _CharT, _Traits >::ignore(), std::basic_streambuf< char_type, traits_type >::snextc(), and std::basic_istream< _CharT, char_traits< _CharT > >::unget().

---

🔥 template<typename _CharT, typename _Traits> basic_filebuf< _CharT, _Traits >::pos_type std::basic_filebuf< _CharT, _Traits >::seekoff (off_type , ios_base::seekdir , ios_base::openmode = ios_base::in | ios_base::out) [protected], [virtual]

Alters the stream positions. Each derived class provides its own appropriate behavior.

Note: the base class version does nothing, returns a pos_type that represents an invalid stream position. (It's giving "I simply will not" energy 😭)

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References _M_destroy_pback(), _M_reading, std::ios_base::cur, is_open(), std::basic_streambuf< _CharT, _Traits >::pbase(), and std::basic_streambuf< _CharT, _Traits >::pptr().

Referenced by imbue(), open(), and pbackfail().

---

⭐ template<typename _CharT, typename _Traits> basic_filebuf< _CharT, _Traits >::pos_type std::basic_filebuf< _CharT, _Traits >::seekpos (pos_type , ios_base::openmode = ios_base::in | ios_base::out) [protected], [virtual]

Alters the stream positions. Each derived class provides its own appropriate behavior.

Note: the base class version does nothing, returns a pos_type that represents an invalid stream position. (Same unbothered base-class behavior as seekoff 💀)

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References _M_destroy_pback(), std::ios_base::beg, and is_open().

---

🧚 template<typename _CharT, typename _Traits> basic_filebuf< _CharT, _Traits >::__streambuf_type * std::basic_filebuf< _CharT, _Traits >::setbuf (char_type * __s, streamsize __n) [protected], [virtual]

Manipulates the buffer.

Parameters

• __s — Pointer to a buffer area.
• __n — Size of __s.

Returns

• this

If no file has been opened, and both __s and __n are zero, then the stream becomes unbuffered. Otherwise, __s is used as a buffer; see https://gcc.gnu.org/onlinedocs/libstdc++/manual/streambufs.html#io.streambuf.buffering for more. (Yes bestie, a whole link, go read it fr fr 📖)

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References _M_buf, _M_buf_size, and is_open().

---

🌸 template<typename _CharT, typename _Traits> void std::basic_streambuf< _CharT, _Traits >::setg (char_type * __gbeg, char_type * __gnext, char_type * __gend) [inline], [protected], [inherited]

Setting the three read area pointers.

Parameters

• __gbeg — A pointer.
• __gnext — A pointer.
• __gend — A pointer.

Postcondition

• __gbeg == eback(), __gnext == gptr(), and __gend == egptr()

Referenced by std::wbuffer_convert< _Codecvt, _Elem, _Tr >::wbuffer_convert(), std::basic_filebuf< char_type, traits_type >::_M_create_pback(), std::basic_filebuf< char_type, traits_type >::_M_destroy_pback(), std::basic_filebuf< char_type, traits_type >::_M_set_buffer(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), and std::basic_filebuf< _CharT, _Traits >::xsgetn().

---

💖 template<typename _CharT, typename _Traits> void std::basic_streambuf< _CharT, _Traits >::setp (char_type * __pbeg, char_type * __pend) [inline], [protected], [inherited]

Setting the three write area pointers.

Parameters

• __pbeg — A pointer.
• __pend — A pointer.

Postcondition

• __pbeg == pbase(), __pbeg == pptr(), and __pend == epptr()

Referenced by std::wbuffer_convert< _Codecvt, _Elem, _Tr >::wbuffer_convert(), and std::basic_filebuf< char_type, traits_type >::_M_set_buffer().

---

🦋 template<typename _CharT, typename _Traits> int_type std::basic_streambuf< _CharT, _Traits >::sgetc () [inline], [inherited]

Getting the next character.

Returns

• The next character, or eof.

If the input read position is available, returns that character, otherwise calls and returns underflow(). Does not move the read position after fetching the character. (It looks, but doesn't touch 🙈)

Referenced by std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_istream< _CharT, char_traits< _CharT > >::readsome(), and std::basic_streambuf< char_type, traits_type >::snextc().

---

🎀 template<typename _CharT, typename _Traits> streamsize std::basic_streambuf< _CharT, _Traits >::sgetn (char_type * __s, streamsize __n) [inline], [inherited]

Entry point for xsgetn.

Parameters

• __s — A buffer area.
• __n — A count.

…okay so this one literally just hands the whole thing off to xsgetn(__s,__n) and calls it a day 💅. The effect is to fill __s[0] through __s[__n-1] with characters from the input sequence, if possible. That's it. That's the whole entire vibe 🫶

---

🌈 showmanyc() [protected], [virtual]

template<typename _CharT, typename _Traits> streamsize std::basic_filebuf< _CharT, _Traits >::showmanyc () [protected],  [virtual]

Investigating the data available. 🔍✨ Bestie is literally just doing recon on how much data is sitting there.

Returns: An estimate of the number of characters available in the input sequence, or -1. 😭

So here's the tea: if it returns a positive value, then successive calls to underflow() will not return traits::eof() until at least that number of characters have been supplied. If showmanyc() returns -1, then calls to underflow() or uflow() will fail. [27.5.2.4.3]/1

Note: 📝

• Base class version does nothing, returns zero.
• The standard adds that the intention is not only that the calls [to underflow or uflow] will not return eof() but that they will return immediately.
• The standard adds that the morphemes of showmanyc are es-how-many-see, not show-manic. 💀 not "show-manic", bestie, we are not diagnosing anyone.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References: _M_mode, std::ios_base::binary, std::basic_streambuf< _CharT, _Traits >::egptr(), std::basic_streambuf< _CharT, _Traits >::gptr(), std::ios_base::in, and is_open().

---

⭐ snextc() [inline], [inherited]

template<typename _CharT, typename _Traits> int_type std::basic_streambuf< _CharT, _Traits >::snextc () [inline],  [inherited]

Getting the next character. 👑

Returns: The next character, or eof.

It calls sbumpc(), and if that function returns traits::eof(), so does this function. Otherwise, sgetc(). Simple as that, no cap. ✨

Referenced by: std::basic_istream< _CharT, char_traits< _CharT > >::get(), std::basic_iostream< char_type, traits_type >::ignore(), and std::basic_istream< _CharT, char_traits< _CharT > >::readsome().

---

🎀 sputbackc(char_type __c) [inline], [inherited]

template<typename _CharT, typename _Traits> int_type std::basic_streambuf< _CharT, _Traits >::sputbackc (char_type __c) [inline],  [inherited]

Pushing characters back into the input stream. 🙈 It's giving "nvm, putting that back."

Parameters:

• __c — The character to push back.

Returns: The previous character, if possible.

Similar to sungetc(), but __c is pushed onto the stream instead of the previous character. If successful, the next character fetched from the input stream will be __c. 👑

Referenced by: std::basic_istream< _CharT, _Traits >::putback().

---

💖 sputc(char_type __c) [inline], [inherited]

template<typename _CharT, typename _Traits> int_type std::basic_streambuf< _CharT, _Traits >::sputc (char_type __c) [inline],  [inherited]

Entry point for all single-character output functions. ✨ Like, the main character of output, fr fr.

Parameters:

• __c — A character to output.

Returns: __c, if possible.

One of two public output functions.

If a write position is available for the output sequence (i.e., the buffer is not full), stores __c in that position, increments the position, and returns traits::to_int_type(__c). If a write position is not available, returns overflow(__c). No drama, just mechanics 💅

Referenced by: std::wbuffer_convert< _Codecvt, _Elem, _Tr >::overflow().

---

🦋 sputn(const char_type * __s, streamsize __n) [inline], [inherited]

template<typename _CharT, typename _Traits> streamsize std::basic_streambuf< _CharT, _Traits >::sputn (const char_type * __s, streamsize __n) [inline],  [inherited]

Entry point for all single-character output functions. (yes bestie, same one-liner as sputc, that's just how the docs be)

Parameters:

• __s — A buffer read area.
• __n — A count.

One of two public output functions.

Returns xsputn(__s,__n). The effect is to write __s[0] through __s[__n-1] to the output sequence, if possible. 🫶

---

🌸 sungetc() [inline], [inherited]

template<typename _CharT, typename _Traits> int_type std::basic_streambuf< _CharT, _Traits >::sungetc () [inline],  [inherited]

Moving backwards in the input stream. 🚶‍♀️⬅️ iconic behaviour honestly.

Returns: The previous character, if possible.

If a putback position is available, this function decrements the input pointer and returns that character. Otherwise, calls and returns pbackfail(). The effect is to unget the last character gotten. 😌

Referenced by: std::basic_istream< _CharT, _Traits >::unget().

---

✨ sync() [protected], [virtual]

template<typename _CharT, typename _Traits> int std::basic_filebuf< _CharT, _Traits >::sync () [protected],  [virtual]

Synchronizes the buffer arrays with the controlled sequences. 💅 getting everything in alignment, as it should be.

Returns: -1 on failure. 😭

Each derived class provides its own appropriate behavior, including the definition of failure. (very "you do you, but define your own failure" of it)

Note: 📝

• Base class version does nothing, returns zero.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References: overflow(), std::basic_streambuf< _CharT, _Traits >::pbase(), and std::basic_streambuf< _CharT, _Traits >::pptr().

---

🧚 uflow() [inline], [protected], [virtual], [inherited]

template<typename _CharT, typename _Traits> virtual int_type std::basic_streambuf< _CharT, _Traits >::uflow () [inline],  [protected],  [virtual],  [inherited]

Fetches more data from the controlled sequence. 🔥

Returns: The first character from the pending sequence.

Informally, this function does the same thing as underflow(), and in fact is required to call that function. It also returns the new character, like underflow() does. However, this function also moves the read position forward by one. So like, same energy, extra step 👑

Reimplemented in __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >.

Referenced by: std::basic_streambuf< char_type, traits_type >::sbumpc(), and xsgetn().

---

🍓 underflow() [protected], [virtual]

template<typename _CharT, typename _Traits> basic_filebuf< _CharT, _Traits >::int_type std::basic_filebuf< _CharT, _Traits >::underflow () [protected],  [virtual]

Fetches more data from the controlled sequence. 🔍

Returns: The first character from the pending sequence.

Informally, this function is called when the input buffer is exhausted (or does not exist, as buffering need not actually be done). If a buffer exists, it is refilled. In either case, the next available character is returned, or traits::eof() to indicate a null pending sequence. 😭

For a formal definition of the pending sequence, see a good text such as Langer & Kreft, or [27.5.2.4.3]/7-14.

A functioning input streambuf can be created by overriding only this function (no buffer area will be used). For an example, see https://gcc.gnu.org/onlinedocs/libstdc++/manual/streambufs.html — bestie that's the cheat code, iykyk 🫶

Note: 📝

• Base class version does nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References: _M_buf_size, _M_destroy_pback(), _M_mode, _M_set_buffer(), std::basic_streambuf< _CharT, _Traits >::eback(), std::basic_streambuf< _CharT, _Traits >::egptr(), std::basic_streambuf< _CharT, _Traits >::gptr(), std::ios_base::in, and overflow().

Referenced by: pbackfail().

---

👑 xsgetn(char_type * __s, streamsize __n) [protected], [virtual]

template<typename _CharT, typename _Traits> streamsize std::basic_filebuf< _CharT, _Traits >::xsgetn (char_type * __s, streamsize __n) [protected],  [virtual]

Multiple character extraction. 💅 the group-chat version of getting characters.

Parameters:

• __s — A buffer area.
• __n — Maximum number of characters to assign.

Returns: The number of characters assigned.

Fills __s[0] through __s[__n-1] with characters from the input sequence, as if by sbumpc(). Stops when either __n characters have been copied, or when traits::eof() would be copied. ✨

It is expected that derived classes provide a more efficient implementation by overriding this definition. (so like, do better than the base, bestie, you got this)

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References: _M_buf_size, _M_destroy_pback(), _M_mode, _M_pback_init, _M_reading, _M_set_buffer(), std::basic_streambuf< _CharT, _Traits >::eback(), std::basic_streambuf< _CharT, _Traits >::egptr(), std::basic_streambuf< _CharT, _Traits >::gbump(), std::basic_streambuf< _CharT, _Traits >::gptr(), std::ios_base::in, overflow(), std::basic_streambuf< _CharT, _Traits >::setg(), and std::basic_streambuf< char_type, traits_type >::xsgetn().

---

🌈 xsputn(const char_type * __s, streamsize __n) [protected], [virtual]

template<typename _CharT, typename _Traits> streamsize std::basic_filebuf< _CharT, _Traits >::xsputn (const char_type * __s, streamsize __n) [protected],  [virtual]

Multiple character insertion. 💖 the output-side twin, obsessed.

Parameters:

• __s — A buffer area.
• __n — Maximum number of characters to write.

Returns: The number of characters written.

Writes __s[0] through __s[__n-1] to the output sequence, as if by sputc(). Stops when either n characters have been copied, or when sputc() would return traits::eof(). 🫶

It is expected that derived classes provide a more efficient implementation by overriding this definition. fr fr, level up if you can ⭐

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

References: _M_buf_size, _M_mode, _M_reading, _M_set_buffer(), std::ios_base::app, std::basic_streambuf< _CharT, _Traits >::epptr(), std::ios_base::out, std::basic_streambuf< _CharT, _Traits >::pbase(), std::basic_streambuf< _CharT, _Traits >::pptr(), and std::basic_streambuf< char_type, traits_type >::xsputn().

💖 Member Data Documentation 💖

Okay so these are the protected data members, bestie — the backstage pass to std::basic_filebuf and its inherited std::basic_streambuf lore. Every single one matters. No cap.

---

🦋 _M_buf 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_filebuf< _CharT, _Traits >::_M_buf [protected]

Pointer to the beginning of the internal buffer — the origin story.

Referenced by basic_filebuf(), and setbuf().

---

🦋 _M_buf_locale 🦋

template<typename _CharT, typename _Traits> locale std::basic_streambuf< _CharT, _Traits >::_M_buf_locale [protected],  [inherited]

Current locale setting. Inherited energy, still iconic.

Referenced by std::basic_filebuf< _CharT, _Traits >::basic_filebuf().

---

🦋 _M_buf_size 🦋

template<typename _CharT, typename _Traits> size_t std::basic_filebuf< _CharT, _Traits >::_M_buf_size [protected]

Actual size of the internal buffer. This number is equal to the size of the put area + 1 position, reserved for the overflow char of a full area.

Referenced by basic_filebuf(), __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), overflow(), setbuf(), underflow(), xsgetn(), and xsputn().

---

🦋 _M_ext_buf 🦋

template<typename _CharT, typename _Traits> char* std::basic_filebuf< _CharT, _Traits >::_M_ext_buf [protected]

Buffer for external characters. Used for input when codecvt::always_noconv() == false. When valid, this corresponds to eback().

Referenced by basic_filebuf(), and imbue().

---

🦋 _M_ext_buf_size 🦋

template<typename _CharT, typename _Traits> streamsize std::basic_filebuf< _CharT, _Traits >::_M_ext_buf_size [protected]

Size of the buffer held by _M_ext_buf.

Referenced by basic_filebuf().

---

🦋 _M_ext_next 🦋

template<typename _CharT, typename _Traits> const char* std::basic_filebuf< _CharT, _Traits >::_M_ext_next [protected]

Pointers into the buffer held by _M_ext_buf that delimit a subsequence of bytes that have been read but not yet converted. When valid, _M_ext_next corresponds to egptr().

Referenced by basic_filebuf(), and imbue().

---

🦋 _M_in_beg 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_streambuf< _CharT, _Traits >::_M_in_beg [protected],  [inherited]

Start of get area.

---

🦋 _M_in_cur 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_streambuf< _CharT, _Traits >::_M_in_cur [protected],  [inherited]

Current read area.

---

🦋 _M_in_end 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_streambuf< _CharT, _Traits >::_M_in_end [protected],  [inherited]

End of get area.

---

🦋 _M_mode 🦋

template<typename _CharT, typename _Traits> ios_base::openmode std::basic_filebuf< _CharT, _Traits >::_M_mode [protected]

Place to stash in || out || in | out settings for current filebuf.

Referenced by basic_filebuf(), __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), close(), imbue(), open(), overflow(), pbackfail(), showmanyc(), underflow(), xsgetn(), and xsputn().

---

🦋 _M_out_beg 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_streambuf< _CharT, _Traits >::_M_out_beg [protected],  [inherited]

Start of put area.

---

🦋 _M_out_cur 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_streambuf< _CharT, _Traits >::_M_out_cur [protected],  [inherited]

Current put area.

---

🦋 _M_out_end 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_streambuf< _CharT, _Traits >::_M_out_end [protected],  [inherited]

End of put area.

---

🦋 _M_pback 🦋

template<typename _CharT, typename _Traits> char_type std::basic_filebuf< _CharT, _Traits >::_M_pback [protected]

Necessary bits for putback buffer management.

Note: pbacks of over one character are not currently supported.

Referenced by basic_filebuf().

---

🦋 _M_pback_cur_save 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_filebuf< _CharT, _Traits >::_M_pback_cur_save [protected]

Necessary bits for putback buffer management.

Note: pbacks of over one character are not currently supported.

Referenced by basic_filebuf().

---

🦋 _M_pback_end_save 🦋

template<typename _CharT, typename _Traits> char_type* std::basic_filebuf< _CharT, _Traits >::_M_pback_end_save [protected]

Necessary bits for putback buffer management.

Note: pbacks of over one character are not currently supported.

Referenced by basic_filebuf().

---

🦋 _M_pback_init 🦋

template<typename _CharT, typename _Traits> bool std::basic_filebuf< _CharT, _Traits >::_M_pback_init [protected]

Necessary bits for putback buffer management.

Note: pbacks of over one character are not currently supported.

Referenced by basic_filebuf(), close(), pbackfail(), and xsgetn().

---

🦋 _M_reading 🦋

template<typename _CharT, typename _Traits> bool std::basic_filebuf< _CharT, _Traits >::_M_reading [protected]

_M_reading == false && _M_writing == false for uncommitted mode; _M_reading == true for read mode; _M_writing == true for write mode;

NB: _M_reading == true && _M_writing == true is unused.

Referenced by basic_filebuf(), __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf(), close(), imbue(), open(), overflow(), pbackfail(), seekoff(), xsgetn(), and xsputn().

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🫶 Author 🫶

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Footer vibe check: this page is from libstdc++, titled std::basic..., _Traits >(3), and the date is whatever Doxygen stamped at generation time. The original footer didn't show a date here, but the source/version energy is 100% libstdc++. Stay iconic, bestie. 💖