std::basic_ifstream< _CharT, _Traits > Class Template Reference
[I/O]

Controlling input for files.

This class supports reading from named files, using the inherited functions from std::basic_istream. To control the associated sequence, an instance of std::basic_filebuf is used, which this page refers to as sb. More...

Inheritance diagram for std::basic_ifstream< _CharT, _Traits >:

List of all members.

Public Types

typedef ctype< _CharT > __ctype_type
typedef basic_filebuf
< char_type, traits_type > __filebuf_type
typedef basic_ios< _CharT,
_Traits > __ios_type
typedef basic_istream
< char_type, traits_type > __istream_type
typedef num_get< _CharT,
istreambuf_iterator< _CharT,
_Traits > > __num_get_type
typedef basic_streambuf
< _CharT, _Traits > __streambuf_type

typedef _CharT char_type

typedef num_put< _CharT,
ostreambuf_iterator< _CharT,
_Traits > > __num_put_type

Public Member Functions

const locale & _M_getloc () const
void _M_setstate (iostate __state)
bool bad () const
basic_ifstream (const std::string &__s, ios_base::openmode __mode=ios_base::in)
basic_ifstream (const char *__s, ios_base::openmode __mode=ios_base::in)
basic_ifstream ()
void clear (iostate __state=goodbit)
void close ()
basic_ios & copyfmt (const basic_ios &__rhs)
bool eof () const
void exceptions (iostate __except)
iostate exceptions () const
bool fail () const
char_type fill (char_type __ch)
char_type fill () const
fmtflags flags (fmtflags __fmtfl)
fmtflags flags () const
streamsize gcount () const
locale getloc () const
bool good () const
locale imbue (const locale &__loc)
bool is_open () const
bool is_open ()
long & iword (int __ix)
char narrow (char_type __c, char __dfault) const
void open (const std::string &__s, ios_base::openmode __mode=ios_base::in)
void open (const char *__s, ios_base::openmode __mode=ios_base::in)
streamsize precision (streamsize __prec)
streamsize precision () const
void *& pword (int __ix)
basic_streambuf< _CharT,
_Traits > * rdbuf (basic_streambuf< _CharT, _Traits > *__sb)
__filebuf_type * rdbuf () const
iostate rdstate () const
void register_callback (event_callback __fn, int __index)
fmtflags setf (fmtflags __fmtfl, fmtflags __mask)
fmtflags setf (fmtflags __fmtfl)
void setstate (iostate __state)
basic_ostream< _CharT, _Traits > * tie (basic_ostream< _CharT, _Traits > *__tiestr)
basic_ostream< _CharT, _Traits > * tie () const
void unsetf (fmtflags __mask)
char_type widen (char __c) const
streamsize width (streamsize __wide)
streamsize width () const
~basic_ifstream ()

Unformatted Input Functions

All the unformatted input functions have some common behavior. Each starts by constructing a temporary object of type std::basic_istream::sentry with the second argument (noskipws) set to true. This has several effects, concluding with the setting of a status flag; see the sentry documentation for more.

If the sentry status is good, the function tries to extract whatever data is appropriate for the type of the argument.

The number of characters extracted is stored for later retrieval by gcount().

If an exception is thrown during extraction, ios_base::badbit will be turned on in the stream's error state without causing an ios_base::failure to be thrown. The original exception will then be rethrown.

__istream_type & get (__streambuf_type &__sb)
__istream_type & get (__streambuf_type &__sb, char_type __delim)
__istream_type & get (char_type *__s, streamsize __n)
__istream_type & get (char_type *__s, streamsize __n, char_type __delim)
__istream_type & get (char_type &__c)
int_type get ()
__istream_type & getline (char_type *__s, streamsize __n)
__istream_type & getline (char_type *__s, streamsize __n, char_type __delim)
__istream_type & ignore (streamsize __n, int_type __delim)
__istream_type & ignore (streamsize __n)
__istream_type & ignore ()
int_type peek ()
__istream_type & putback (char_type __c)
__istream_type & read (char_type *__s, streamsize __n)
streamsize readsome (char_type *__s, streamsize __n)
__istream_type & seekg (off_type, ios_base::seekdir)
__istream_type & seekg (pos_type)
int sync ()
pos_type tellg ()
__istream_type & unget ()

operator void * () const
bool operator! () const

Arithmetic Extractors

All the operator>> functions (aka formatted input functions) have some common behavior. Each starts by constructing a temporary object of type std::basic_istream::sentry with the second argument (noskipws) set to false. This has several effects, concluding with the setting of a status flag; see the sentry documentation for more.

If the sentry status is good, the function tries to extract whatever data is appropriate for the type of the argument.

If an exception is thrown during extraction, ios_base::badbit will be turned on in the stream's error state without causing an ios_base::failure to be thrown. The original exception will then be rethrown.

__istream_type & operator>> (__streambuf_type *__sb)
__istream_type & operator>> (void *&__p)
__istream_type & operator>> (long double &__f)
__istream_type & operator>> (double &__f)
__istream_type & operator>> (float &__f)
__istream_type & operator>> (unsigned long long &__n)
__istream_type & operator>> (long long &__n)
__istream_type & operator>> (unsigned long &__n)
__istream_type & operator>> (long &__n)
__istream_type & operator>> (unsigned int &__n)
__istream_type & operator>> (int &__n)
__istream_type & operator>> (unsigned short &__n)
__istream_type & operator>> (short &__n)
__istream_type & operator>> (bool &__n)

__istream_type & operator>> (ios_base &(*__pf)(ios_base &))
__istream_type & operator>> (__ios_type &(*__pf)(__ios_type &))
__istream_type & operator>> (__istream_type &(*__pf)(__istream_type &))

Static Public Member Functions

static bool sync_with_stdio (bool __sync=true)
static int xalloc () throw ()

Static Public Attributes

static const fmtflags adjustfield
static const openmode app
static const openmode ate
static const iostate badbit
static const fmtflags basefield
static const seekdir beg
static const openmode binary
static const fmtflags boolalpha
static const seekdir cur
static const fmtflags dec
static const seekdir end
static const iostate eofbit
static const iostate failbit
static const fmtflags fixed
static const fmtflags floatfield
static const iostate goodbit
static const fmtflags hex
static const openmode in
static const fmtflags internal
static const fmtflags left
static const fmtflags oct
static const openmode out
static const fmtflags right
static const fmtflags scientific
static const fmtflags showbase
static const fmtflags showpoint
static const fmtflags showpos
static const fmtflags skipws
static const openmode trunc
static const fmtflags unitbuf
static const fmtflags uppercase

Protected Types

enum { _S_local_word_size }

Protected Member Functions

void _M_cache_locale (const locale &__loc)
void _M_call_callbacks (event __ev) throw ()
void _M_dispose_callbacks (void)
__istream_type & _M_extract (_ValueT &__v)
_Words & _M_grow_words (int __index, bool __iword)
void _M_init ()
void init (basic_streambuf< _CharT, _Traits > *__sb)

Protected Attributes

_Callback_list * _M_callbacks
const __ctype_type * _M_ctype
char_type _M_fill
bool _M_fill_init
streamsize _M_gcount
locale _M_ios_locale
_Words _M_local_word [_S_local_word_size]
const __num_get_type * _M_num_get
const __num_put_type * _M_num_put
basic_streambuf< _CharT,
_Traits > * _M_streambuf
basic_ostream< _CharT, _Traits > * _M_tie
_Words * _M_word
int _M_word_size
_Words _M_word_zero

Friends

class sentry

Detailed Description

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

Controlling input for files.

This class supports reading from named files, using the inherited functions from std::basic_istream. To control the associated sequence, an instance of std::basic_filebuf is used, which this page refers to as sb.

Definition at line 414 of file fstream.

Member Typedef Documentation

typedef ctype<_CharT > std::basic_istream< _CharT , _Traits >::__ctype_type [inherited]

These are non-standard types.

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

Definition at line 71 of file istream.

typedef num_get<_CharT , istreambuf_iterator<_CharT , _Traits > > std::basic_istream< _CharT , _Traits >::__num_get_type [inherited]

These are non-standard types.

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

Definition at line 70 of file istream.

typedef num_put<_CharT , ostreambuf_iterator<_CharT , _Traits > > std::basic_ios< _CharT , _Traits >::__num_put_type [inherited]

These are non-standard types.

Reimplemented in std::basic_ostream< _CharT, _Traits >, and std::basic_ostream< _CharT, _Traits >.

Definition at line 84 of file basic_ios.h.

template<typename _CharT , typename _Traits >

typedef _CharT std::basic_ifstream< _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_istream< _CharT, _Traits >.

Definition at line 418 of file fstream.

typedef void(* std::ios_base::event_callback)(event, ios_base &, int) [inherited]

The type of an event callback function.

Parameters:

	event	One of the members of the event enum.
	ios_base	Reference to the ios_base object.
	int	The integer provided when the callback was registered.

Event callbacks are user defined functions that get called during several ios_base and basic_ios functions, specifically imbue(), copyfmt(), and ~ios().

typedef _Ios_Fmtflags std::ios_base::fmtflags [inherited]

This is a bitmask type.

"_Ios_Fmtflags" is implementation-defined, but it is valid to perform bitwise operations on these values and expect the Right Thing to happen. Defined objects of type fmtflags are:

boolalpha
dec
fixed
hex
internal
left
oct
right
scientific
showbase
showpoint
showpos
skipws
unitbuf
uppercase
adjustfield
basefield
floatfield

Definition at line 263 of file ios_base.h.

template<typename _CharT , typename _Traits >

typedef traits_type::int_type std::basic_ifstream< _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_istream< _CharT, _Traits >.

Definition at line 420 of file fstream.

typedef _Ios_Iostate std::ios_base::iostate [inherited]

This is a bitmask type.

"_Ios_Iostate" is implementation-defined, but it is valid to perform bitwise operations on these values and expect the Right Thing to happen. Defined objects of type iostate are:

badbit
eofbit
failbit
goodbit

Definition at line 338 of file ios_base.h.

template<typename _CharT , typename _Traits >

typedef traits_type::off_type std::basic_ifstream< _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_istream< _CharT, _Traits >.

Definition at line 422 of file fstream.

typedef _Ios_Openmode std::ios_base::openmode [inherited]

This is a bitmask type.

"_Ios_Openmode" is implementation-defined, but it is valid to perform bitwise operations on these values and expect the Right Thing to happen. Defined objects of type openmode are:

app
ate
binary
in
out
trunc

Definition at line 369 of file ios_base.h.

template<typename _CharT , typename _Traits >

typedef traits_type::pos_type std::basic_ifstream< _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_istream< _CharT, _Traits >.

Definition at line 421 of file fstream.

typedef _Ios_Seekdir std::ios_base::seekdir [inherited]

This is an enumerated type.

"_Ios_Seekdir" is implementation-defined. Defined values of type seekdir are:

beg
cur, equivalent to SEEK_CUR in the C standard library.
end, equivalent to SEEK_END in the C standard library.

Definition at line 401 of file ios_base.h.

template<typename _CharT , typename _Traits >

typedef _Traits std::basic_ifstream< _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_istream< _CharT, _Traits >.

Definition at line 419 of file fstream.

Member Enumeration Documentation

enum std::ios_base::event [inherited]

The set of events that may be passed to an event callback.

erase_event is used during ~ios() and copyfmt(). imbue_event is used during imbue(). copyfmt_event is used during copyfmt().

Definition at line 427 of file ios_base.h.

Constructor & Destructor Documentation

template<typename _CharT , typename _Traits >

std::basic_ifstream< _CharT, _Traits >::basic_ifstream ( ) [inline]

Default constructor.

Initializes sb using its default constructor, and passes &sb to the base class initializer. Does not open any files (you haven't given it a filename to open).

Definition at line 440 of file fstream.

template<typename _CharT , typename _Traits >

std::basic_ifstream< _CharT, _Traits >::basic_ifstream	(	const char *	__s,
		ios_base::openmode	__mode = `ios_base::in`
	)			`[inline, explicit]`

Create an input file stream.

Parameters:

	s	Null terminated string specifying the filename.
	mode	Open file in specified mode (see std::ios_base).

ios_base::in is automatically included in mode.

Tip: When using std::string to hold the filename, you must use .c_str() before passing it to this constructor.

Definition at line 454 of file fstream.

template<typename _CharT , typename _Traits >

std::basic_ifstream< _CharT, _Traits >::basic_ifstream	(	const std::string &	__s,
		ios_base::openmode	__mode = `ios_base::in`
	)			`[inline, explicit]`

Create an input file stream.

Parameters:

	s	std::string specifying the filename.
	mode	Open file in specified mode (see std::ios_base).

ios_base::in is automatically included in mode.

Definition at line 470 of file fstream.

template<typename _CharT , typename _Traits >

std::basic_ifstream< _CharT, _Traits >::~basic_ifstream ( ) [inline]

The destructor does nothing.

The file is closed by the filebuf object, not the formatting stream.

Definition at line 485 of file fstream.

Member Function Documentation

const locale& std::ios_base::_M_getloc ( ) const [inline, inherited]

Locale access.

Returns:: A reference to the current locale.

Like getloc above, but returns a reference instead of generating a copy.

Definition at line 710 of file ios_base.h.

Referenced by std::money_get< _CharT, _InIter >::do_get(), std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_date(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::time_get< _CharT, _InIter >::do_get_time(), std::time_get< _CharT, _InIter >::do_get_weekday(), std::time_get< _CharT, _InIter >::do_get_year(), std::time_put< _CharT, _OutIter >::do_put(), std::num_put< _CharT, _OutIter >::do_put(), and std::time_put< _CharT, _OutIter >::put().

bool std::basic_ios< _CharT , _Traits >::bad ( ) const [inline, inherited]

Fast error checking.

Returns:: True if the badbit is set.

Note that other iostate flags may also be set.

Definition at line 201 of file basic_ios.h.

void std::basic_ios< _CharT , _Traits >::clear ( iostate __state = goodbit ) [inherited]

[Re]sets the error state.

Parameters:

state

The new state flag(s) to set.

See std::ios_base::iostate for the possible bit values. Most users will not need to pass an argument.

template<typename _CharT , typename _Traits >

void std::basic_ifstream< _CharT, _Traits >::close ( ) [inline]

Close the file.

Calls std::basic_filebuf::close(). If that function fails, failbit is set in the stream's error state.

Definition at line 563 of file fstream.

basic_ios& std::basic_ios< _CharT , _Traits >::copyfmt ( const basic_ios< _CharT, _Traits > & __rhs ) [inherited]

Copies fields of __rhs into this.

Parameters:

__rhs

The source values for the copies.

Returns:: Reference to this object.

All fields of __rhs are copied into this object except that rdbuf() and rdstate() remain unchanged. All values in the pword and iword arrays are copied. Before copying, each callback is invoked with erase_event. After copying, each (new) callback is invoked with copyfmt_event. The final step is to copy exceptions().

bool std::basic_ios< _CharT , _Traits >::eof ( ) const [inline, inherited]

Fast error checking.

Returns:: True if the eofbit is set.

Note that other iostate flags may also be set.

Definition at line 180 of file basic_ios.h.

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

void std::basic_ios< _CharT , _Traits >::exceptions ( iostate __except ) [inline, inherited]

Throwing exceptions on errors.

Parameters:

except

The new exceptions mask.

By default, error flags are set silently. You can set an exceptions mask for each stream; if a bit in the mask becomes set in the error flags, then an exception of type std::ios_base::failure is thrown.

If the error flag is already set when the exceptions mask is added, the exception is immediately thrown. Try running the following under GCC 3.1 or later:

  #include <iostream>
  #include <fstream>
  #include <exception>

  int main()
  {
      std::set_terminate (__gnu_cxx::__verbose_terminate_handler);

      std::ifstream f ("/etc/motd");

      std::cerr << "Setting badbit\n";
      f.setstate (std::ios_base::badbit);

      std::cerr << "Setting exception mask\n";
      f.exceptions (std::ios_base::badbit);
  }

Definition at line 247 of file basic_ios.h.

iostate std::basic_ios< _CharT , _Traits >::exceptions ( ) const [inline, inherited]

Throwing exceptions on errors.

Returns:: The current exceptions mask.

This changes nothing in the stream. See the one-argument version of exceptions(iostate) for the meaning of the return value.

Definition at line 212 of file basic_ios.h.

bool std::basic_ios< _CharT , _Traits >::fail ( ) const [inline, inherited]

Fast error checking.

Returns:: True if either the badbit or the failbit is set.

Checking the badbit in fail() is historical practice. Note that other iostate flags may also be set.

Definition at line 191 of file basic_ios.h.

Referenced by std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_ostream< _CharT, _Traits >::seekp(), and std::basic_ostream< _CharT, _Traits >::tellp().

char_type std::basic_ios< _CharT , _Traits >::fill ( char_type __ch ) [inline, inherited]

Sets a new "empty" character.

Parameters:

ch

The new character.

Returns:: The previous fill character.

The fill character is used to fill out space when P+ characters have been requested (e.g., via setw), Q characters are actually used, and Q<P. It defaults to a space (' ') in the current locale.

Definition at line 380 of file basic_ios.h.

char_type std::basic_ios< _CharT , _Traits >::fill ( ) const [inline, inherited]

Retrieves the "empty" character.

Returns:: The current fill character.

It defaults to a space (' ') in the current locale.

Definition at line 360 of file basic_ios.h.

fmtflags std::ios_base::flags ( fmtflags __fmtfl ) [inline, inherited]

Setting new format flags all at once.

Parameters:

fmtfl

The new flags to set.

Returns:: The previous format control flags.

This function overwrites all the format flags with fmtfl.

Definition at line 566 of file ios_base.h.

fmtflags std::ios_base::flags ( ) const [inline, inherited]

Access to format flags.

Returns:: The format control flags for both input and output.

Definition at line 555 of file ios_base.h.

Referenced by std::basic_ios< _CharT, _Traits >::copyfmt(), std::num_get< _CharT, _InIter >::do_get(), std::num_put< _CharT, _OutIter >::do_put(), std::basic_ostream< _CharT, _Traits >::operator<<(), and std::operator<<().

streamsize std::basic_istream< _CharT , _Traits >::gcount ( ) const [inline, inherited]

Character counting.

Returns:: The number of characters extracted by the previous unformatted input function dispatched for this stream.

Definition at line 248 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::get ( __streambuf_type & __sb ) [inline, inherited]

Extraction into another streambuf.

Parameters:

sb

A streambuf in which to store data.

Returns:: *this

Returns get(sb,widen('
')).

Definition at line 365 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::get	(	__streambuf_type &	__sb,
		char_type	__delim
	)			`[inherited]`

Extraction into another streambuf.

Parameters:

	sb	A streambuf in which to store data.
	delim	A "stop" character.

Returns:: *this

Characters are extracted and inserted into sb until one of the following happens:

the input sequence reaches EOF
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted)
the next character equals delim (in this case, the character is not extracted)
an exception occurs (and in this case is caught)

If no characters are stored, failbit is set in the stream's error state.

__istream_type& std::basic_istream< _CharT , _Traits >::get	(	char_type *	__s,
		streamsize	__n
	)			`[inline, inherited]`

Simple multiple-character extraction.

Parameters:

	s	Pointer to an array.
	n	Maximum number of characters to store in s.

Returns:: *this

Returns get(s,n,widen('
')).

Definition at line 332 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::get	(	char_type *	__s,
		streamsize	__n,
		char_type	__delim
	)			`[inherited]`

Simple multiple-character extraction.

Parameters:

	s	Pointer to an array.
	n	Maximum number of characters to store in s.
	delim	A "stop" character.

Returns:: *this

Characters are extracted and stored into s until one of the following happens:

n-1 characters are stored
the input sequence reaches EOF
the next character equals delim, in which case the character is not extracted

If no characters are stored, failbit is set in the stream's error state.

In any case, a null character is stored into the next location in the array.

Note:: This function is not overloaded on signed char and unsigned char.

__istream_type& std::basic_istream< _CharT , _Traits >::get ( char_type & __c ) [inherited]

Simple extraction.

Parameters:

c

The character in which to store data.

Returns:: *this

Tries to extract a character and store it in c. If none are available, sets failbit and returns traits::eof().

Note:: This function is not overloaded on signed char and unsigned char.

int_type std::basic_istream< _CharT , _Traits >::get ( void ) [inherited]

Simple extraction.

Returns:: A character, or eof().

Tries to extract a character. If none are available, sets failbit and returns traits::eof().

__istream_type& std::basic_istream< _CharT , _Traits >::getline	(	char_type *	__s,
		streamsize	__n
	)			`[inline, inherited]`

String extraction.

Parameters:

	s	A character array in which to store the data.
	n	Maximum number of characters to extract.

Returns:: *this

Returns getline(s,n,widen('
')).

Definition at line 405 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::getline	(	char_type *	__s,
		streamsize	__n,
		char_type	__delim
	)			`[inherited]`

String extraction.

Parameters:

	s	A character array in which to store the data.
	n	Maximum number of characters to extract.
	delim	A "stop" character.

Returns:: *this

Extracts and stores characters into s until one of the following happens. Note that these criteria are required to be tested in the order listed here, to allow an input line to exactly fill the s array without setting failbit.

the input sequence reaches end-of-file, in which case eofbit is set in the stream error state
the next character equals delim, in which case the character is extracted (and therefore counted in gcount()) but not stored
n-1 characters are stored, in which case failbit is set in the stream error state

If no characters are extracted, failbit is set. (An empty line of input should therefore not cause failbit to be set.)

In any case, a null character is stored in the next location in the array.

locale std::ios_base::getloc ( ) const [inline, inherited]

Locale access.

Returns:: A copy of the current locale.

If imbue(loc) has previously been called, then this function returns loc. Otherwise, it returns a copy of std::locale(), the global C++ locale.

Definition at line 699 of file ios_base.h.

Referenced by std::basic_ios< _CharT, _Traits >::copyfmt(), std::money_put< _CharT, _OutIter >::do_put(), std::basic_ios< _CharT, _Traits >::imbue(), std::operator>>(), and std::ws().

bool std::basic_ios< _CharT , _Traits >::good ( ) const [inline, inherited]

Fast error checking.

Returns:: True if no error flags are set.

A wrapper around rdstate.

Definition at line 170 of file basic_ios.h.

__istream_type& std::basic_istream< _CharT , _Traits >::ignore	(	streamsize	__n,
		int_type	__delim
	)			`[inherited]`

Extraction into another streambuf.

Parameters:

sb

A streambuf in which to store data.

Returns:: *this

Returns get(sb,widen('
')).

__istream_type& std::basic_istream< _CharT , _Traits >::ignore ( streamsize __n ) [inherited]

Extraction into another streambuf.

Parameters:

sb

A streambuf in which to store data.

Returns:: *this

Returns get(sb,widen('
')).

__istream_type& std::basic_istream< _CharT , _Traits >::ignore ( void ) [inherited]

Discarding characters.

Parameters:

	n	Number of characters to discard.
	delim	A "stop" character.

Returns:: *this

Extracts characters and throws them away until one of the following happens:

if n != std::numeric_limits<int>::max(), n characters are extracted
the input sequence reaches end-of-file
the next character equals delim (in this case, the character is extracted); note that this condition will never occur if delim equals traits::eof().

NB: Provide three overloads, instead of the single function (with defaults) mandated by the Standard: this leads to a better performing implementation, while still conforming to the Standard.

locale std::basic_ios< _CharT , _Traits >::imbue ( const locale & __loc ) [inherited]

Moves to a new locale.

Parameters:

loc

The new locale.

Returns:: The previous locale.

Calls ios_base::imbue(loc), and if a stream buffer is associated with this stream, calls that buffer's pubimbue(loc).

Additional l10n notes are at http://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html

Reimplemented from std::ios_base.

Referenced by std::operator<<().

void std::basic_ios< _CharT , _Traits >::init ( basic_streambuf< _CharT , _Traits > * __sb ) [protected, inherited]

All setup is performed here.

This is called from the public constructor. It is not virtual and cannot be redefined.

template<typename _CharT , typename _Traits >

bool std::basic_ifstream< _CharT, _Traits >::is_open ( ) [inline]

Wrapper to test for an open file.

Returns:: rdbuf()->is_open()

Definition at line 504 of file fstream.

long& std::ios_base::iword ( int __ix ) [inline, inherited]

Access to integer array.

Parameters:

__ix

Index into the array.

Returns:: A reference to an integer associated with the index.

The iword function provides access to an array of integers that can be used for any purpose. The array grows as required to hold the supplied index. All integers in the array are initialized to 0.

The implementation reserves several indices. You should use xalloc to obtain an index that is safe to use. Also note that since the array can grow dynamically, it is not safe to hold onto the reference.

Definition at line 745 of file ios_base.h.

char std::basic_ios< _CharT , _Traits >::narrow	(	char_type	__c,
		char	__dfault
	)			const `[inline, inherited]`

Squeezes characters.

Parameters:

	c	The character to narrow.
	dfault	The character to narrow.

Returns:: The narrowed character.

Maps a character of char_type to a character of char, if possible.

Returns the result of

    std::use_facet<ctype<char_type> >(getloc()).narrow(c,dfault)

Additional l10n notes are at http://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html

Definition at line 420 of file basic_ios.h.

template<typename _CharT , typename _Traits >

void std::basic_ifstream< _CharT, _Traits >::open	(	const std::string &	__s,
		ios_base::openmode	__mode = `ios_base::in`
	)			`[inline]`

Opens an external file.

Parameters:

	s	The name of the file.
	mode	The open mode flags.

Calls std::basic_filebuf::open(s,mode|in). If that function fails, failbit is set in the stream's error state.

Definition at line 545 of file fstream.

template<typename _CharT , typename _Traits >

void std::basic_ifstream< _CharT, _Traits >::open	(	const char *	__s,
		ios_base::openmode	__mode = `ios_base::in`
	)			`[inline]`

Opens an external file.

Parameters:

	s	The name of the file.
	mode	The open mode flags.

Calls std::basic_filebuf::open(s,mode|in). If that function fails, failbit is set in the stream's error state.

Tip: When using std::string to hold the filename, you must use .c_str() before passing it to this constructor.

Definition at line 525 of file fstream.

std::basic_ios< _CharT , _Traits >::operator void * ( ) const [inline, inherited]

The quick-and-easy status check.

This allows you to write constructs such as "if (!a_stream) ..." and "while (a_stream) ..."

Definition at line 111 of file basic_ios.h.

bool std::basic_ios< _CharT , _Traits >::operator! ( ) const [inline, inherited]

The quick-and-easy status check.

This allows you to write constructs such as "if (!a_stream) ..." and "while (a_stream) ..."

Definition at line 115 of file basic_ios.h.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( __streambuf_type * __sb ) [inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( void *& __p ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 214 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( long double & __f ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 210 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( double & __f ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 206 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( float & __f ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 202 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( unsigned long long & __n ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 197 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( long long & __n ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 193 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( unsigned long & __n ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 188 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( long & __n ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 184 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( unsigned int & __n ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 180 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( int & __n ) [inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( unsigned short & __n ) [inline, inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

Definition at line 173 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( short & __n ) [inherited]

Extracting into another streambuf.

Parameters:

sb

A pointer to a streambuf

This function behaves like one of the basic arithmetic extractors, in that it also constructs a sentry object and has the same error handling behavior.

If sb is NULL, the stream will set failbit in its error state.

Characters are extracted from this stream and inserted into the sb streambuf until one of the following occurs:

the input stream reaches end-of-file,
insertion into the output buffer fails (in this case, the character that would have been inserted is not extracted), or
an exception occurs (and in this case is caught)

If the function inserts no characters, failbit is set.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( bool & __n ) [inline, inherited]

Basic arithmetic extractors.

Parameters:

A

variable of builtin type.

Returns:: *this if successful

These functions use the stream's current locale (specifically, the num_get facet) to parse the input data.

Definition at line 166 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( ios_base &(*)(ios_base &) __pf ) [inline, inherited]

Interface for manipulators.

Manipulators such as std::ws and std::dec use these functions in constructs like "std::cin >> std::ws". For more information, see the iomanip header.

Definition at line 130 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( __ios_type &(*)(__ios_type &) __pf ) [inline, inherited]

Interface for manipulators.

Manipulators such as std::ws and std::dec use these functions in constructs like "std::cin >> std::ws". For more information, see the iomanip header.

Definition at line 123 of file istream.

__istream_type& std::basic_istream< _CharT , _Traits >::operator>> ( __istream_type &(*)(__istream_type &) __pf ) [inline, inherited]

Interface for manipulators.

Manipulators such as std::ws and std::dec use these functions in constructs like "std::cin >> std::ws". For more information, see the iomanip header.

Definition at line 119 of file istream.

int_type std::basic_istream< _CharT , _Traits >::peek ( void ) [inherited]

Looking ahead in the stream.

Returns:: The next character, or eof().

If, after constructing the sentry object, good() is false, returns traits::eof(). Otherwise reads but does not extract the next input character.

streamsize std::ios_base::precision ( streamsize __prec ) [inline, inherited]

Changing flags.

Parameters:

prec

The new precision value.

Returns:: The previous value of precision().

Definition at line 634 of file ios_base.h.

streamsize std::ios_base::precision ( ) const [inline, inherited]

Flags access.

Returns:: The precision to generate on certain output operations.

Be careful if you try to give a definition of "precision" here; see DR 189.

Definition at line 625 of file ios_base.h.

Referenced by std::basic_ios< _CharT, _Traits >::copyfmt(), and std::operator<<().

__istream_type& std::basic_istream< _CharT , _Traits >::putback ( char_type __c ) [inherited]

Unextracting a single character.

Parameters:

c

The character to push back into the input stream.

Returns:: *this

If rdbuf() is not null, calls rdbuf()->sputbackc(c).

If rdbuf() is null or if sputbackc() fails, sets badbit in the error state.

Note:: Since no characters are extracted, the next call to gcount() will return 0, as required by DR 60.

void*& std::ios_base::pword ( int __ix ) [inline, inherited]

Access to void pointer array.

Parameters:

__ix

Index into the array.

Returns:: A reference to a void* associated with the index.

The pword function provides access to an array of pointers that can be used for any purpose. The array grows as required to hold the supplied index. All pointers in the array are initialized to 0.

The implementation reserves several indices. You should use xalloc to obtain an index that is safe to use. Also note that since the array can grow dynamically, it is not safe to hold onto the reference.

Definition at line 766 of file ios_base.h.

basic_streambuf<_CharT , _Traits >* std::basic_ios< _CharT , _Traits >::rdbuf ( basic_streambuf< _CharT , _Traits > * __sb ) [inherited]

Changing the underlying buffer.

Parameters:

sb

The new stream buffer.

Returns:: The previous stream buffer.

Associates a new buffer with the current stream, and clears the error state.

Due to historical accidents which the LWG refuses to correct, the I/O library suffers from a design error: this function is hidden in derived classes by overrides of the zero-argument rdbuf(), which is non-virtual for hysterical raisins. As a result, you must use explicit qualifications to access this function via any derived class. For example:

  std::fstream     foo;         // or some other derived type
  std::streambuf*  p = .....;

  foo.ios::rdbuf(p);            // ios == basic_ios<char>

template<typename _CharT , typename _Traits >

__filebuf_type* std::basic_ifstream< _CharT, _Traits >::rdbuf ( ) const [inline]

Accessing the underlying buffer.

Returns:: The current basic_filebuf buffer.

This hides both signatures of std::basic_ios::rdbuf().

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

Definition at line 496 of file fstream.

iostate std::basic_ios< _CharT , _Traits >::rdstate ( ) const [inline, inherited]

Returns the error state of the stream buffer.

Returns:: A bit pattern (well, isn't everything?)

See std::ios_base::iostate for the possible bit values. Most users will call one of the interpreting wrappers, e.g., good().

Definition at line 127 of file basic_ios.h.

__istream_type& std::basic_istream< _CharT , _Traits >::read	(	char_type *	__s,
		streamsize	__n
	)			`[inherited]`

Extraction without delimiters.

Parameters:

	s	A character array.
	n	Maximum number of characters to store.

Returns:: *this

If the stream state is good(), extracts characters and stores them into s until one of the following happens:

n characters are stored
the input sequence reaches end-of-file, in which case the error state is set to failbit|eofbit.

Note:: This function is not overloaded on signed char and unsigned char.

streamsize std::basic_istream< _CharT , _Traits >::readsome	(	char_type *	__s,
		streamsize	__n
	)			`[inherited]`

Extraction until the buffer is exhausted, but no more.

Parameters:

	s	A character array.
	n	Maximum number of characters to store.

Returns:: The number of characters extracted.

Extracts characters and stores them into s depending on the number of characters remaining in the streambuf's buffer, rdbuf()->in_avail(), called A here:

if A == -1, sets eofbit and extracts no characters
if A == 0, extracts no characters
if A > 0, extracts min(A,n)

The goal is to empty the current buffer, and to not request any more from the external input sequence controlled by the streambuf.

void std::ios_base::register_callback	(	event_callback	__fn,
		int	__index
	)			`[inherited]`

Add the callback __fn with parameter __index.

Parameters:

	__fn	The function to add.
	__index	The integer to pass to the function when invoked.

Registers a function as an event callback with an integer parameter to be passed to the function when invoked. Multiple copies of the function are allowed. If there are multiple callbacks, they are invoked in the order they were registered.

__istream_type& std::basic_istream< _CharT , _Traits >::seekg	(	off_type	,
		ios_base::seekdir
	)			`[inherited]`

Changing the current read position.

Parameters:

	off	A file offset object.
	dir	The direction in which to seek.

Returns:: *this

If fail() is not true, calls rdbuf()->pubseekoff(off,dir). If that function fails, sets failbit.

Note:: This function does not count the number of characters extracted, if any, and therefore does not affect the next call to gcount().

__istream_type& std::basic_istream< _CharT , _Traits >::seekg ( pos_type ) [inherited]

Changing the current read position.

Parameters:

pos

A file position object.

Returns:: *this

If fail() is not true, calls rdbuf()->pubseekpos(pos). If that function fails, sets failbit.

Note:: This function does not count the number of characters extracted, if any, and therefore does not affect the next call to gcount().

fmtflags std::ios_base::setf	(	fmtflags	__fmtfl,
		fmtflags	__mask
	)			`[inline, inherited]`

Setting new format flags.

Parameters:

	fmtfl	Additional flags to set.
	mask	The flags mask for fmtfl.

Returns:: The previous format control flags.

This function clears mask in the format flags, then sets fmtfl & mask. An example mask is ios_base::adjustfield.

Definition at line 599 of file ios_base.h.

fmtflags std::ios_base::setf ( fmtflags __fmtfl ) [inline, inherited]

Setting new format flags.

Parameters:

fmtfl

Additional flags to set.

Returns:: The previous format control flags.

This function sets additional flags in format control. Flags that were previously set remain set.

Definition at line 582 of file ios_base.h.

Referenced by std::boolalpha(), std::dec(), std::fixed(), std::hex(), std::internal(), std::left(), std::oct(), std::right(), std::scientific(), std::showbase(), std::showpoint(), std::showpos(), std::skipws(), std::unitbuf(), and std::uppercase().

void std::basic_ios< _CharT , _Traits >::setstate ( iostate __state ) [inline, inherited]

Sets additional flags in the error state.

Parameters:

state

The additional state flag(s) to set.

See std::ios_base::iostate for the possible bit values.

Definition at line 147 of file basic_ios.h.

Referenced by std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_ostream< _CharT, _Traits >::seekp(), and std::basic_istream< _CharT, _Traits >::sync().

int std::basic_istream< _CharT , _Traits >::sync ( void ) [inherited]

Synchronizing the stream buffer.

Returns:: 0 on success, -1 on failure

If rdbuf() is a null pointer, returns -1.

Otherwise, calls rdbuf()->pubsync(), and if that returns -1, sets badbit and returns -1.

Otherwise, returns 0.

Note:: This function does not count the number of characters extracted, if any, and therefore does not affect the next call to gcount().

static bool std::ios_base::sync_with_stdio ( bool __sync = true ) [static, inherited]

Interaction with the standard C I/O objects.

Parameters:

sync

Whether to synchronize or not.

Returns:: True if the standard streams were previously synchronized.

The synchronization referred to is only that between the standard C facilities (e.g., stdout) and the standard C++ objects (e.g., cout). User-declared streams are unaffected. See http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch28s02.html

pos_type std::basic_istream< _CharT , _Traits >::tellg ( void ) [inherited]

Getting the current read position.

Returns:: A file position object.

If fail() is not false, returns pos_type(-1) to indicate failure. Otherwise returns rdbuf()->pubseekoff(0,cur,in).

Note:: This function does not count the number of characters extracted, if any, and therefore does not affect the next call to gcount().

basic_ostream<_CharT , _Traits >* std::basic_ios< _CharT , _Traits >::tie ( basic_ostream< _CharT , _Traits > * __tiestr ) [inline, inherited]

Ties this stream to an output stream.

Parameters:

tiestr

The output stream.

Returns:: The previously tied output stream, or NULL if the stream was not tied.

This sets up a new tie; see tie() for more.

Definition at line 297 of file basic_ios.h.

basic_ostream<_CharT , _Traits >* std::basic_ios< _CharT , _Traits >::tie ( ) const [inline, inherited]

Fetches the current tied stream.

Returns:: A pointer to the tied stream, or NULL if the stream is not tied.

A stream may be tied (or synchronized) to a second output stream. When this stream performs any I/O, the tied stream is first flushed. For example, std::cin is tied to std::cout.

Definition at line 285 of file basic_ios.h.

__istream_type& std::basic_istream< _CharT , _Traits >::unget ( void ) [inherited]

Unextracting the previous character.

Returns:: *this

If rdbuf() is not null, calls rdbuf()->sungetc(c).

If rdbuf() is null or if sungetc() fails, sets badbit in the error state.

Note:: Since no characters are extracted, the next call to gcount() will return 0, as required by DR 60.

void std::ios_base::unsetf ( fmtflags __mask ) [inline, inherited]

Clearing format flags.

Parameters:

mask

The flags to unset.

This function clears mask in the format flags.

Definition at line 614 of file ios_base.h.

Referenced by std::noboolalpha(), std::noshowbase(), std::noshowpoint(), std::noshowpos(), std::noskipws(), std::nounitbuf(), and std::nouppercase().

char_type std::basic_ios< _CharT , _Traits >::widen ( char __c ) const [inline, inherited]

Widens characters.

Parameters:

c

The character to widen.

Returns:: The widened character.

Maps a character of char to a character of char_type.

Returns the result of

    std::use_facet<ctype<char_type> >(getloc()).widen(c)

Additional l10n notes are at http://gcc.gnu.org/onlinedocs/libstdc++/manual/localization.html

Definition at line 439 of file basic_ios.h.

streamsize std::ios_base::width ( streamsize __wide ) [inline, inherited]

Changing flags.

Parameters:

wide

The new width value.

Returns:: The previous value of width().

Definition at line 657 of file ios_base.h.

streamsize std::ios_base::width ( ) const [inline, inherited]

Flags access.

Returns:: The minimum field width to generate on output operations.

"Minimum field width" refers to the number of characters.

Definition at line 648 of file ios_base.h.

Referenced by std::basic_ios< _CharT, _Traits >::copyfmt(), std::num_put< _CharT, _OutIter >::do_put(), and std::operator>>().

static int std::ios_base::xalloc ( ) throw () [static, inherited]

Access to unique indices.

Returns:: An integer different from all previous calls.

This function returns a unique integer every time it is called. It can be used for any purpose, but is primarily intended to be a unique index for the iword and pword functions. The expectation is that an application calls xalloc in order to obtain an index in the iword and pword arrays that can be used without fear of conflict.

The implementation maintains a static variable that is incremented and returned on each invocation. xalloc is guaranteed to return an index that is safe to use in the iword and pword arrays.

Member Data Documentation

iostate std::ios_base::_M_exception [protected, inherited]

ios_base data members (doc me)

Definition at line 467 of file ios_base.h.

fmtflags std::ios_base::_M_flags [protected, inherited]

ios_base data members (doc me)

Definition at line 466 of file ios_base.h.

streamsize std::basic_istream< _CharT , _Traits >::_M_gcount [protected, inherited]

The number of characters extracted in the previous unformatted function; see gcount().

Definition at line 79 of file istream.

streamsize std::ios_base::_M_precision [protected, inherited]

ios_base data members (doc me)

Definition at line 464 of file ios_base.h.

iostate std::ios_base::_M_streambuf_state [protected, inherited]

ios_base data members (doc me)

Definition at line 468 of file ios_base.h.

streamsize std::ios_base::_M_width [protected, inherited]

ios_base data members (doc me)

Definition at line 465 of file ios_base.h.

const fmtflags std::ios_base::adjustfield [static, inherited]

A mask of left|right|internal. Useful for the 2-arg form of setf.

Definition at line 318 of file ios_base.h.

Referenced by std::num_put< _CharT, _OutIter >::do_put().

const openmode std::ios_base::app [static, inherited]

Seek to end before each write.

Definition at line 372 of file ios_base.h.

const openmode std::ios_base::ate [static, inherited]

Open and seek to end immediately after opening.

Definition at line 375 of file ios_base.h.

const iostate std::ios_base::badbit [static, inherited]

Indicates a loss of integrity in an input or output sequence (such as an irrecoverable read error from a file).

Definition at line 342 of file ios_base.h.

const fmtflags std::ios_base::basefield [static, inherited]

A mask of dec|oct|hex. Useful for the 2-arg form of setf.

Definition at line 321 of file ios_base.h.

Referenced by std::num_get< _CharT, _InIter >::do_get(), and std::basic_ostream< _CharT, _Traits >::operator<<().

const seekdir std::ios_base::beg [static, inherited]

Request a seek relative to the beginning of the stream.

Definition at line 404 of file ios_base.h.

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

const openmode std::ios_base::binary [static, inherited]

Perform input and output in binary mode (as opposed to text mode). This is probably not what you think it is; see http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch27s02.html.

Definition at line 380 of file ios_base.h.

const fmtflags std::ios_base::boolalpha [static, inherited]

Insert/extract bool in alphabetic rather than numeric format.

Definition at line 266 of file ios_base.h.

Referenced by std::num_get< _CharT, _InIter >::do_get(), and std::num_put< _CharT, _OutIter >::do_put().

const seekdir std::ios_base::cur [static, inherited]

Request a seek relative to the current position within the sequence.

Definition at line 407 of file ios_base.h.

Referenced by std::basic_filebuf< _CharT, _Traits >::imbue(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), and std::basic_ostream< _CharT, _Traits >::tellp().

const fmtflags std::ios_base::dec [static, inherited]

Converts integer input or generates integer output in decimal base.

Definition at line 269 of file ios_base.h.

const seekdir std::ios_base::end [static, inherited]

Request a seek relative to the current end of the sequence.

Definition at line 410 of file ios_base.h.

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

const iostate std::ios_base::eofbit [static, inherited]

Indicates that an input operation reached the end of an input sequence.

Definition at line 345 of file ios_base.h.

Referenced by std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_date(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_istream< _CharT, _Traits >::operator>>(), and std::basic_istream< _CharT, _Traits >::read().

const iostate std::ios_base::failbit [static, inherited]

Indicates that an input operation failed to read the expected characters, or that an output operation failed to generate the desired characters.

Definition at line 350 of file ios_base.h.

Referenced by std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::basic_istream< _CharT, _Traits >::get(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::basic_istream< _CharT, _Traits >::operator>>(), std::operator>>(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::seekg(), and std::basic_ostream< _CharT, _Traits >::seekp().

const fmtflags std::ios_base::fixed [static, inherited]

Generate floating-point output in fixed-point notation.

Definition at line 272 of file ios_base.h.

const fmtflags std::ios_base::floatfield [static, inherited]

A mask of scientific|fixed. Useful for the 2-arg form of setf.

Definition at line 324 of file ios_base.h.

const iostate std::ios_base::goodbit [static, inherited]

Indicates all is well.

Definition at line 353 of file ios_base.h.

const fmtflags std::ios_base::hex [static, inherited]

Converts integer input or generates integer output in hexadecimal base.

Definition at line 275 of file ios_base.h.

Referenced by std::num_get< _CharT, _InIter >::do_get(), std::num_put< _CharT, _OutIter >::do_put(), and std::basic_ostream< _CharT, _Traits >::operator<<().

const openmode std::ios_base::in [static, inherited]

Open for input. Default for ifstream and fstream.

Definition at line 383 of file ios_base.h.

Referenced by std::basic_istream< _CharT, _Traits >::seekg(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::underflow(), std::basic_filebuf< _CharT, _Traits >::underflow(), and std::basic_filebuf< _CharT, _Traits >::xsgetn().

const fmtflags std::ios_base::internal [static, inherited]

Adds fill characters at a designated internal point in certain generated output, or identical to right if no such point is designated.

Definition at line 280 of file ios_base.h.

const fmtflags std::ios_base::left [static, inherited]

Adds fill characters on the right (final positions) of certain generated output. (I.e., the thing you print is flush left.).

Definition at line 284 of file ios_base.h.

Referenced by std::num_put< _CharT, _OutIter >::do_put().

const fmtflags std::ios_base::oct [static, inherited]

Converts integer input or generates integer output in octal base.

Definition at line 287 of file ios_base.h.

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

const openmode std::ios_base::out [static, inherited]

Open for output. Default for ofstream and fstream.

Definition at line 386 of file ios_base.h.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), and std::basic_ostream< _CharT, _Traits >::tellp().

const fmtflags std::ios_base::right [static, inherited]

Adds fill characters on the left (initial positions) of certain generated output. (I.e., the thing you print is flush right.).

Definition at line 291 of file ios_base.h.

const fmtflags std::ios_base::scientific [static, inherited]

Generates floating-point output in scientific notation.

Definition at line 294 of file ios_base.h.

const fmtflags std::ios_base::showbase [static, inherited]

Generates a prefix indicating the numeric base of generated integer output.

Definition at line 298 of file ios_base.h.

const fmtflags std::ios_base::showpoint [static, inherited]

Generates a decimal-point character unconditionally in generated floating-point output.

Definition at line 302 of file ios_base.h.

const fmtflags std::ios_base::showpos [static, inherited]

Generates a + sign in non-negative generated numeric output.

Definition at line 305 of file ios_base.h.

const fmtflags std::ios_base::skipws [static, inherited]

Skips leading white space before certain input operations.

Definition at line 308 of file ios_base.h.

const openmode std::ios_base::trunc [static, inherited]

Open for input. Default for ofstream.

Definition at line 389 of file ios_base.h.

const fmtflags std::ios_base::unitbuf [static, inherited]

Flushes output after each output operation.

Definition at line 311 of file ios_base.h.

const fmtflags std::ios_base::uppercase [static, inherited]

Replaces certain lowercase letters with their uppercase equivalents in generated output.

Definition at line 315 of file ios_base.h.

Referenced by std::num_put< _CharT, _OutIter >::do_put().

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

fstream

std::basic_ifstream< _CharT, _Traits > Class Template Reference [I/O]

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Types

Protected Member Functions

Protected Attributes

Friends

Detailed Description

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

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation

std::basic_ifstream< _CharT, _Traits > Class Template Reference
[I/O]

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