libstdc++
__gnu_cxx::stdio_filebuf< _CharT, _Traits > Class Template Reference
Inheritance diagram for __gnu_cxx::stdio_filebuf< _CharT, _Traits >:

List of all members.

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Friends


Detailed Description

template<typename _CharT, typename _Traits = std::char_traits<_CharT>>
class __gnu_cxx::stdio_filebuf< _CharT, _Traits >

Provides a layer of compatibility for C/POSIX.

This GNU extension provides extensions for working with standard C FILE*'s and POSIX file descriptors. It must be instantiated by the user with the type of character used in the file stream, e.g., stdio_filebuf<char>.

Definition at line 51 of file stdio_filebuf.h.


Member Typedef Documentation

template<typename _CharT, typename _Traits>
typedef basic_streambuf<char_type, traits_type> std::basic_filebuf< _CharT, _Traits >::__streambuf_type [inherited]

This is a non-standard type.

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

Definition at line 79 of file fstream.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
typedef _CharT __gnu_cxx::stdio_filebuf< _CharT, _Traits >::char_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

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

Definition at line 55 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
typedef traits_type::int_type __gnu_cxx::stdio_filebuf< _CharT, _Traits >::int_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

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

Definition at line 57 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
typedef traits_type::off_type __gnu_cxx::stdio_filebuf< _CharT, _Traits >::off_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

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

Definition at line 59 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
typedef traits_type::pos_type __gnu_cxx::stdio_filebuf< _CharT, _Traits >::pos_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

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

Definition at line 58 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
typedef _Traits __gnu_cxx::stdio_filebuf< _CharT, _Traits >::traits_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

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

Definition at line 56 of file stdio_filebuf.h.


Constructor & Destructor Documentation

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
__gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf ( ) [inline]

deferred initialization

Definition at line 66 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits >
__gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf ( int  __fd,
std::ios_base::openmode  __mode,
size_t  __size = static_cast<size_t>(BUFSIZ) 
)
Parameters:
__fdAn open file descriptor.
__modeSame meaning as in a standard filebuf.
__sizeOptimal or preferred size of internal buffer, in chars.

This constructor associates a file stream buffer with an open POSIX file descriptor. The file descriptor will be automatically closed when the stdio_filebuf is closed/destroyed.

Definition at line 129 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits >
__gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf ( std::__c_file *  __f,
std::ios_base::openmode  __mode,
size_t  __size = static_cast<size_t>(BUFSIZ) 
)
Parameters:
__fAn open FILE*.
__modeSame meaning as in a standard filebuf.
__sizeOptimal or preferred size of internal buffer, in chars. Defaults to system's BUFSIZ.

This constructor associates a file stream buffer with an open C FILE*. The FILE* will not be automatically closed when the stdio_filebuf is closed/destroyed.

Definition at line 145 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits >
__gnu_cxx::stdio_filebuf< _CharT, _Traits >::~stdio_filebuf ( ) [virtual]

Closes the external data stream if the file descriptor constructor was used.

Definition at line 124 of file stdio_filebuf.h.


Member Function Documentation

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

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

Definition at line 174 of file fstream.

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

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

Definition at line 191 of file fstream.

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

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.

Definition at line 392 of file fstream.

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

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.

Definition at line 130 of file fstream.tcc.

Referenced by std::basic_ifstream< _CharT, _Traits >::close(), std::basic_ofstream< _CharT, _Traits >::close(), std::basic_fstream< _CharT, _Traits >::close(), and std::basic_filebuf< char_type, traits_type >::~basic_filebuf().

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

Definition at line 480 of file streambuf.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_destroy_pback(), std::basic_streambuf< char_type, traits_type >::sputbackc(), and std::basic_streambuf< char_type, traits_type >::sungetc().

template<typename _CharT, typename _Traits>
char_type* std::basic_streambuf< _CharT, _Traits >::egptr ( ) 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

Definition at line 486 of file streambuf.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_create_pback(), std::basic_streambuf< char_type, traits_type >::in_avail(), std::basic_streambuf< char_type, traits_type >::sbumpc(), std::basic_streambuf< char_type, traits_type >::sgetc(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::showmanyc(), and std::basic_stringbuf< _CharT, _Traits, _Alloc >::str().

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

Access to the put area.

These functions are only available to other protected functions, including derived classes.

  • 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

Definition at line 533 of file streambuf.

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

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
int __gnu_cxx::stdio_filebuf< _CharT, _Traits >::fd ( ) [inline]
Returns:
The underlying file descriptor.

Once associated with an external data stream, this function can be used to access the underlying POSIX file descriptor. Note that there is no way for the library to track what you do with the descriptor, so be careful.

Definition at line 110 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>>
std::__c_file* __gnu_cxx::stdio_filebuf< _CharT, _Traits >::file ( ) [inline]
Returns:
The underlying FILE*.

This function can be used to access the underlying "C" file pointer. Note that there is no way for the library to track what you do with the file, so be careful.

Definition at line 120 of file stdio_filebuf.h.

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

Moving the read position.

Parameters:
__nThe delta by which to move.

This just advances the read position without returning any data.

Definition at line 496 of file streambuf.

Referenced by std::basic_streambuf< char_type, traits_type >::sbumpc(), std::basic_streambuf< char_type, traits_type >::sputbackc(), std::basic_streambuf< char_type, traits_type >::sungetc(), and std::basic_streambuf< char_type, traits_type >::uflow().

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

Locale access.

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.

Definition at line 224 of file streambuf.

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

template<typename _CharT, typename _Traits>
char_type* std::basic_streambuf< _CharT, _Traits >::gptr ( ) const [inline, protected, inherited]
template<typename _CharT , typename _Traits >
void std::basic_filebuf< _CharT, _Traits >::imbue ( const locale __loc) [protected, virtual, inherited]

Changes translations.

Parameters:
__locA 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 >.

Definition at line 912 of file fstream.tcc.

References std::ios_base::cur.

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

Looking ahead into the stream.

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().

Definition at line 282 of file streambuf.

template<typename _CharT, typename _Traits>
bool std::basic_filebuf< _CharT, _Traits >::is_open ( ) const throw () [inline, inherited]
template<typename _CharT , typename _Traits >
basic_filebuf< _CharT, _Traits >::__filebuf_type * std::basic_filebuf< _CharT, _Traits >::open ( const char *  __s,
ios_base::openmode  __mode 
) [inherited]

Opens an external file.

Parameters:
__sThe name of the file.
__modeThe 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) +---------------------------------------------------------+ | ios_base Flag combination stdio equivalent | |binary in out trunc app | +---------------------------------------------------------+ | + w | | + + a | | + a | | + + w | | + r | | + + r+ | | + + + w+ | | + + + a+ | | + + a+ | +---------------------------------------------------------+ | + + wb | | + + + ab | | + + ab | | + + + wb | | + + rb | | + + + r+b | | + + + + w+b | | + + + + a+b | | + + + a+b | +---------------------------------------------------------+

Definition at line 96 of file fstream.tcc.

References std::ios_base::ate, std::ios_base::end, and std::basic_filebuf< _CharT, _Traits >::open().

Referenced by std::basic_filebuf< _CharT, _Traits >::open(), std::basic_ifstream< _CharT, _Traits >::open(), std::basic_ofstream< _CharT, _Traits >::open(), and std::basic_fstream< _CharT, _Traits >::open().

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

Opens an external file.

Parameters:
__sThe name of the file.
__modeThe open mode flags.
Returns:
this on success, NULL on failure

Definition at line 277 of file fstream.

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

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

Consumes data from the buffer; writes to the controlled sequence.

Parameters:
__cAn additional character to consume.
Returns:
eof() to indicate failure, something else (usually __c, or not_eof())

Informally, this function is called when the output buffer is full (or does not exist, as buffering need not actually be done). If a buffer exists, it is consumed, with some effect on the controlled sequence. (Typically, the buffer is written out to the sequence verbatim.) In either case, the character c is also written out, if __c is not eof().

For a formal definition of this function, see a good text such as Langer & Kreft, or [27.5.2.4.5]/3-7.

A functioning output streambuf can be created by overriding only this function (no buffer area will be used).

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

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

Definition at line 424 of file fstream.tcc.

References std::ios_base::cur, and std::ios_base::out.

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

Tries to back up the input sequence.

Parameters:
__cThe 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:
Base class version does nothing, returns eof().

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

Definition at line 365 of file fstream.tcc.

References std::ios_base::cur, and std::ios_base::in.

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.

  • 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

Definition at line 527 of file streambuf.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::str().

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

Moving the write position.

Parameters:
__nThe delta by which to move.

This just advances the write position without returning any data.

Definition at line 543 of file streambuf.

Referenced by 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.

  • 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

Definition at line 530 of file streambuf.

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

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

Entry point for imbue().

Parameters:
__locThe new locale.
Returns:
The previous locale.

Calls the derived imbue(__loc).

Definition at line 207 of file streambuf.

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:
__offOffset.
__wayValue for ios_base::seekdir.
__modeValue for ios_base::openmode.

Calls virtual seekoff function.

Definition at line 249 of file streambuf.

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:
__spPosition
__modeValue for ios_base::openmode.

Calls virtual seekpos function.

Definition at line 261 of file streambuf.

template<typename _CharT, typename _Traits>
__streambuf_type* 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.

Definition at line 237 of file streambuf.

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

Calls virtual sync function.

Definition at line 269 of file streambuf.

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().

Definition at line 314 of file streambuf.

Referenced by std::basic_istream< _CharT, _Traits >::getline(), std::basic_istream< _CharT, _Traits >::ignore(), std::istreambuf_iterator< _CharT, _Traits >::operator++(), and std::basic_streambuf< char_type, traits_type >::snextc().

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, inherited]

Alters the stream positions.

Each derived class provides its own appropriate behavior.

Note:
Base class version does nothing, returns a pos_type that represents an invalid stream position.

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

Definition at line 715 of file fstream.tcc.

References std::ios_base::cur.

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, inherited]

Alters the stream positions.

Each derived class provides its own appropriate behavior.

Note:
Base class version does nothing, returns a pos_type that represents an invalid stream position.

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

Definition at line 775 of file fstream.tcc.

References std::ios_base::beg.

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

Manipulates the buffer.

Parameters:
__sPointer to a buffer area.
__nSize 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 http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch25s02.html for more.

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

Definition at line 686 of file fstream.tcc.

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:
__gbegA pointer.
__gnextA pointer.
__gendA pointer.
Postcondition:
__gbeg == eback(), __gnext == gptr(), and __gend == egptr()

Definition at line 507 of file streambuf.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_create_pback(), std::basic_filebuf< char_type, traits_type >::_M_destroy_pback(), and std::basic_filebuf< char_type, traits_type >::_M_set_buffer().

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:
__pbegA pointer.
__pendA pointer.
Postcondition:
__pbeg == pbase(), __pbeg == pptr(), and __pend == epptr()

Definition at line 553 of file streambuf.

Referenced by 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.

Definition at line 336 of file streambuf.

Referenced by std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::getline(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_istream< _CharT, _Traits >::sentry::sentry(), 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:
__sA buffer area.
__nA count.

Returns xsgetn(s,n). The effect is to fill __s[0] through __s[__n-1] with characters from the input sequence, if possible.

Definition at line 355 of file streambuf.

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

Investigating the data available.

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

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.

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

Definition at line 180 of file fstream.tcc.

References std::ios_base::binary, and std::ios_base::in.

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.

Calls sbumpc(), and if that function returns traits::eof(), so does this function. Otherwise, sgetc().

Definition at line 296 of file streambuf.

Referenced by std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::getline(), std::basic_istream< _CharT, _Traits >::ignore(), and std::basic_istream< _CharT, _Traits >::sentry::sentry().

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.

Parameters:
__cThe 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.

Definition at line 370 of file streambuf.

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

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.

Parameters:
__cA 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).

Definition at line 422 of file streambuf.

Referenced by std::basic_istream< _CharT, _Traits >::get(), and std::ostreambuf_iterator< _CharT, _Traits >::operator=().

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.

Parameters:
__sA buffer read area.
__nA 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.

Definition at line 448 of file streambuf.

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

Moving backwards in the input stream.

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.

Definition at line 395 of file streambuf.

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

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

Synchronizes the buffer arrays with the controlled sequences.

Returns:
-1 on failure.

Each derived class provides its own appropriate behavior, including the definition of failure.

Note:
Base class version does nothing, returns zero.

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

Definition at line 895 of file fstream.tcc.

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.

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

Definition at line 698 of file streambuf.

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

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

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 http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch25.html

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

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

Definition at line 206 of file fstream.tcc.

References std::ios_base::in, and std::min().

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

Multiple character extraction.

Parameters:
__sA buffer area.
__nMaximum 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.

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

Definition at line 551 of file fstream.tcc.

References std::ios_base::in.

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

Multiple character insertion.

Parameters:
__sA buffer area.
__nMaximum 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.

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

Definition at line 639 of file fstream.tcc.

References std::min(), and std::ios_base::out.


Member Data Documentation

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

Pointer to the beginning of internal buffer.

Definition at line 111 of file fstream.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_destroy_pback(), and std::basic_filebuf< char_type, traits_type >::_M_set_buffer().

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

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

Definition at line 118 of file fstream.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_set_buffer().

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

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

Definition at line 153 of file fstream.

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

Size of buffer held by _M_ext_buf.

Definition at line 158 of file fstream.

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

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().

Definition at line 165 of file fstream.

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

This is based on _IO_FILE, just reordered to be more consistent, and is intended to be the most minimal abstraction for an internal buffer.

  • get == input == read
  • put == output == write

Definition at line 182 of file streambuf.

Referenced by std::basic_streambuf< char_type, traits_type >::eback(), and std::basic_streambuf< char_type, traits_type >::setg().

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

Entry point for imbue().

Parameters:
__locThe new locale.
Returns:
The previous locale.

Calls the derived imbue(__loc).

Definition at line 183 of file streambuf.

Referenced by std::basic_streambuf< char_type, traits_type >::gbump(), std::basic_streambuf< char_type, traits_type >::gptr(), and std::basic_streambuf< char_type, traits_type >::setg().

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

Entry point for imbue().

Parameters:
__locThe new locale.
Returns:
The previous locale.

Calls the derived imbue(__loc).

Definition at line 184 of file streambuf.

Referenced by std::basic_streambuf< char_type, traits_type >::egptr(), and std::basic_streambuf< char_type, traits_type >::setg().

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

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

Definition at line 96 of file fstream.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_set_buffer().

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

Entry point for imbue().

Parameters:
__locThe new locale.
Returns:
The previous locale.

Calls the derived imbue(__loc).

Definition at line 185 of file streambuf.

Referenced by std::basic_streambuf< char_type, traits_type >::pbase(), and std::basic_streambuf< char_type, traits_type >::setp().

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

Entry point for imbue().

Parameters:
__locThe new locale.
Returns:
The previous locale.

Calls the derived imbue(__loc).

Definition at line 186 of file streambuf.

Referenced by std::basic_streambuf< char_type, traits_type >::pbump(), std::basic_streambuf< char_type, traits_type >::pptr(), and std::basic_streambuf< char_type, traits_type >::setp().

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

Entry point for imbue().

Parameters:
__locThe new locale.
Returns:
The previous locale.

Calls the derived imbue(__loc).

Definition at line 187 of file streambuf.

Referenced by std::basic_streambuf< char_type, traits_type >::epptr(), and std::basic_streambuf< char_type, traits_type >::setp().

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

Necessary bits for putback buffer management.

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

Definition at line 139 of file fstream.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_create_pback().

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

Necessary bits for putback buffer management.

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

Definition at line 140 of file fstream.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_create_pback(), and std::basic_filebuf< char_type, traits_type >::_M_destroy_pback().

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

Necessary bits for putback buffer management.

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

Definition at line 141 of file fstream.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_create_pback(), and std::basic_filebuf< char_type, traits_type >::_M_destroy_pback().

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

Necessary bits for putback buffer management.

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

Definition at line 142 of file fstream.

Referenced by std::basic_filebuf< char_type, traits_type >::_M_create_pback(), and std::basic_filebuf< char_type, traits_type >::_M_destroy_pback().

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

_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.

Definition at line 130 of file fstream.


The documentation for this class was generated from the following file: