Provided by: libstdc++-11-doc_11.4.0-4ubuntu1_all 
NAME
std::wbuffer_convert< _Codecvt, _Elem, _Tr > - Buffer conversions.
SYNOPSIS
#include <locale_conv.h>
Inherits std::basic_streambuf< wchar_t, char_traits< wchar_t > >.
Public Types
typedef _Codecvt::state_type state_type
typedef wchar_t char_type
typedef char_traits< wchar_t > traits_type
typedef traits_type::int_type int_type
typedef traits_type::pos_type pos_type
typedef traits_type::off_type off_type
typedef basic_streambuf< char_type, traits_type > __streambuf_type
This is a non-standard type.
Public Member Functions
wbuffer_convert ()
Default constructor.
wbuffer_convert (const wbuffer_convert &)=delete
wbuffer_convert (streambuf *__bytebuf, _Codecvt *__pcvt=new _Codecvt, state_type
__state=state_type())
locale getloc () const
Locale access.
streamsize in_avail ()
Looking ahead into the stream.
wbuffer_convert & operator= (const wbuffer_convert &)=delete
locale pubimbue (const locale &__loc)
Entry point for imbue().
streambuf * rdbuf () const noexcept
streambuf * rdbuf (streambuf *__bytebuf) noexcept
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.
state_type state () const noexcept
The conversion state following the last conversion.
int_type sungetc ()
Moving backwards in the input stream.
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 gbump (int __n)
Moving the read position.
virtual void imbue (const locale &__loc)
Changes translations.
_Wide_streambuf::int_type overflow (typename _Wide_streambuf::int_type __out)
Consumes data from the buffer; writes to the controlled sequence.
virtual int_type pbackfail (int_type __c=traits_type::eof())
Tries to back up the input sequence.
void pbump (int __n)
Moving the write position.
virtual pos_type seekoff (off_type, ios_base::seekdir,
ios_base::openmode=ios_base::in|ios_base::out)
Alters the stream positions.
virtual pos_type seekpos (pos_type, ios_base::openmode=ios_base::in|ios_base::out)
Alters the stream positions.
virtual basic_streambuf< char_type, char_traits< wchar_t > > * setbuf (char_type *,
streamsize)
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)
int sync ()
Synchronizes the buffer arrays with the controlled sequences.
virtual int_type uflow ()
Fetches more data from the controlled sequence.
_Wide_streambuf::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.
streamsize xsputn (const typename _Wide_streambuf::char_type *__s, streamsize __n)
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
locale _M_buf_locale
Current locale setting.
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.
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.
Detailed Description
template<typename _Codecvt, typename _Elem = wchar_t, typename _Tr = char_traits<_Elem>>
class std::wbuffer_convert< _Codecvt, _Elem, _Tr >"Buffer conversions.
Member Typedef Documentation
typedef basic_streambuf<char_type, traits_type> std::basic_streambuf< wchar_t , char_traits<
wchar_t > >::__streambuf_type [inherited]
This is a non-standard type.
typedef wchar_t std::basic_streambuf< wchar_t , char_traits< wchar_t > >::char_type
[inherited]
These are standard types. They permit a standardized way of referring to names of (or
names dependent on) the template parameters, which are specific to the implementation.
typedef traits_type::int_type std::basic_streambuf< wchar_t , char_traits< wchar_t >
>::int_type [inherited]
These are standard types. They permit a standardized way of referring to names of (or
names dependent on) the template parameters, which are specific to the implementation.
typedef traits_type::off_type std::basic_streambuf< wchar_t , char_traits< wchar_t >
>::off_type [inherited]
These are standard types. They permit a standardized way of referring to names of (or
names dependent on) the template parameters, which are specific to the implementation.
typedef traits_type::pos_type std::basic_streambuf< wchar_t , char_traits< wchar_t >
>::pos_type [inherited]
These are standard types. They permit a standardized way of referring to names of (or
names dependent on) the template parameters, which are specific to the implementation.
typedef char_traits< wchar_t > std::basic_streambuf< wchar_t , char_traits< wchar_t >
>::traits_type [inherited]
These are standard types. They permit a standardized way of referring to names of (or
names dependent on) the template parameters, which are specific to the implementation.
Constructor & Destructor Documentation
template<typename _Codecvt , typename _Elem = wchar_t, typename _Tr = char_traits<_Elem>>
std::wbuffer_convert< _Codecvt, _Elem, _Tr >::wbuffer_convert () [inline]
Default constructor.
template<typename _Codecvt , typename _Elem = wchar_t, typename _Tr = char_traits<_Elem>>
std::wbuffer_convert< _Codecvt, _Elem, _Tr >::wbuffer_convert (streambuf * __bytebuf,
_Codecvt * __pcvt = new _Codecvt, state_type __state = state_type()) [inline], [explicit]
Constructor.
Parameters
__bytebuf The underlying byte stream buffer.
__pcvt The facet to use for conversions.
__state Initial conversion state.
Takes ownership of __pcvt and will delete it in the destructor.
References std::basic_streambuf< wchar_t, char_traits< wchar_t > >::setg(), and
std::basic_streambuf< wchar_t, char_traits< wchar_t > >::setp().
Member Function Documentation
char_type * std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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
char_type * std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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
char_type * std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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
void std::basic_streambuf< wchar_t , char_traits< wchar_t > >::gbump (int __n) [inline],
[protected], [inherited]
Moving the read position.
Parameters
__n The delta by which to move.
This just advances the read position without returning any data.
locale std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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.
char_type * std::basic_streambuf< wchar_t , char_traits< wchar_t > >::gptr () 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
virtual void std::basic_streambuf< wchar_t , char_traits< wchar_t > >::imbue (const locale &
__loc) [inline], [protected], [virtual], [inherited]
Changes translations.
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.
streamsize std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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().
template<typename _Codecvt , typename _Elem = wchar_t, typename _Tr = char_traits<_Elem>>
_Wide_streambuf::int_type std::wbuffer_convert< _Codecvt, _Elem, _Tr >::overflow (typename
_Wide_streambuf::int_type __c) [inline], [protected], [virtual]
Consumes data from the buffer; writes to the controlled sequence.
Parameters
__c An 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< wchar_t, char_traits< wchar_t > >.
References std::basic_streambuf< wchar_t, char_traits< wchar_t > >::sputc().
virtual int_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::pbackfail
(int_type __c = traits_type::eof()) [inline], [protected], [virtual], [inherited]
Tries to back up the input sequence.
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
Base class version does nothing, returns eof().
char_type * std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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
void std::basic_streambuf< wchar_t , char_traits< wchar_t > >::pbump (int __n) [inline],
[protected], [inherited]
Moving the write position.
Parameters
__n The delta by which to move.
This just advances the write position without returning any data.
char_type * std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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
locale std::basic_streambuf< wchar_t , char_traits< wchar_t > >::pubimbue (const locale &
__loc) [inline], [inherited]
Entry point for imbue().
Parameters
__loc The new locale.
Returns
The previous locale.
Calls the derived imbue(__loc).
pos_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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.
pos_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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.
basic_streambuf * std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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.
int std::basic_streambuf< wchar_t , char_traits< wchar_t > >::pubsync () [inline],
[inherited]
Calls virtual sync function.
int_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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().
virtual pos_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::seekoff (off_type,
ios_base::seekdir, ios_base::openmode = ios_base::in | ios_base::out) [inline],
[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.
virtual pos_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::seekpos (pos_type,
ios_base::openmode = ios_base::in | ios_base::out) [inline], [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.
virtual basic_streambuf< char_type, char_traits< wchar_t > > * std::basic_streambuf< wchar_t
, char_traits< wchar_t > >::setbuf (char_type *, streamsize) [inline], [protected],
[virtual], [inherited]
Manipulates the buffer. Each derived class provides its own appropriate behavior. See the
next-to-last paragraph of
https://gcc.gnu.org/onlinedocs/libstdc++/manual/streambufs.html#io.streambuf.buffering for
more on this function.
Note
Base class version does nothing, returns this.
void std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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()
void std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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()
int_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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.
streamsize std::basic_streambuf< wchar_t , char_traits< wchar_t > >::sgetn (char_type * __s,
streamsize __n) [inline], [inherited]
Entry point for xsgetn.
Parameters
__s A buffer area.
__n A count.
Returns xsgetn(__s,__n). The effect is to fill __s[0] through __s[__n-1] with characters
from the input sequence, if possible.
virtual streamsize std::basic_streambuf< wchar_t , char_traits< wchar_t > >::showmanyc ()
[inline], [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.
int_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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().
int_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::sputbackc (char_type __c)
[inline], [inherited]
Pushing characters back into the input stream.
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.
int_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::sputc (char_type __c)
[inline], [inherited]
Entry point for all single-character output functions.
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).
streamsize std::basic_streambuf< wchar_t , char_traits< wchar_t > >::sputn (const char_type *
__s, streamsize __n) [inline], [inherited]
Entry point for all single-character output functions.
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.
template<typename _Codecvt , typename _Elem = wchar_t, typename _Tr = char_traits<_Elem>>
state_type std::wbuffer_convert< _Codecvt, _Elem, _Tr >::state () const [inline],
[noexcept]
The conversion state following the last conversion.
int_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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.
template<typename _Codecvt , typename _Elem = wchar_t, typename _Tr = char_traits<_Elem>>
int std::wbuffer_convert< _Codecvt, _Elem, _Tr >::sync (void) [inline], [protected],
[virtual]
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< wchar_t, char_traits< wchar_t > >.
References std::basic_streambuf< _CharT, _Traits >::pubsync().
virtual int_type std::basic_streambuf< wchar_t , char_traits< wchar_t > >::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.
template<typename _Codecvt , typename _Elem = wchar_t, typename _Tr = char_traits<_Elem>>
_Wide_streambuf::int_type std::wbuffer_convert< _Codecvt, _Elem, _Tr >::underflow ()
[inline], [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
Note
Base class version does nothing, returns eof().
Reimplemented from std::basic_streambuf< wchar_t, char_traits< wchar_t > >.
References std::basic_streambuf< wchar_t, char_traits< wchar_t > >::egptr(), and
std::basic_streambuf< wchar_t, char_traits< wchar_t > >::gptr().
streamsize std::basic_streambuf< wchar_t , char_traits< wchar_t > >::xsgetn (char_type * __s,
streamsize __n) [protected], [virtual], [inherited]
Multiple character extraction.
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.
streamsize std::basic_streambuf< wchar_t , char_traits< wchar_t > >::xsputn (const char_type
* __s, streamsize __n) [protected], [virtual], [inherited]
Multiple character insertion.
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.
Member Data Documentation
locale std::basic_streambuf< wchar_t , char_traits< wchar_t > >::_M_buf_locale [protected],
[inherited]
Current locale setting.
char_type* std::basic_streambuf< wchar_t , char_traits< wchar_t > >::_M_in_beg [protected],
[inherited]
Start of get area.
char_type* std::basic_streambuf< wchar_t , char_traits< wchar_t > >::_M_in_cur [protected],
[inherited]
Current read area.
char_type* std::basic_streambuf< wchar_t , char_traits< wchar_t > >::_M_in_end [protected],
[inherited]
End of get area.
char_type* std::basic_streambuf< wchar_t , char_traits< wchar_t > >::_M_out_beg [protected],
[inherited]
Start of put area.
char_type* std::basic_streambuf< wchar_t , char_traits< wchar_t > >::_M_out_cur [protected],
[inherited]
Current put area.
char_type* std::basic_streambuf< wchar_t , char_traits< wchar_t > >::_M_out_end [protected],
[inherited]
End of put area.
Author
Generated automatically by Doxygen for libstdc++ from the source code.
libstdc++ Wed Sestd::wbuffer_convert< _Codecvt, _Elem, _Tr >(3cxx)