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Ios base c что это

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Ios base c что это

Base class that defines member types and maintains data for classes that inherit from it

Synopsis

Description

The class ios_base defines several member types:

A class failure derived from exception

Three Bitmask Types : fmtflags , iostate , and openmode

Two enumerated types: seekdir and event

It maintains several kinds of data:

Control information that influences how to interpret (format) input sequences and how to generate (format) output sequences

Locale object used within the stream classes

Arrays of user data used for storage management

A number of static constant data members

Additional information that is stored by the program for its private use

Interface

Member Types

The type fmtflags is a bitmask type. See Bitmask Type for more information. Setting its elements has the following effects:

Generates a + sign in nonnegative generated numeric output.

Generates a prefix indicating the numeric base of generated integer output

Replaces certain lowercase letters with their uppercase equivalents in generated output

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

Inserts and extracts bool type in alphabetic format

Flushes output after each output operation

Adds fill characters at a designated internal point in certain generated output. If no such point is designated, it’s identical to right .

Adds fill characters on the right (final positions) of certain generated output

Adds fill characters on the left (initial positions) of certain generated output

Converts integer input or generates integer output in decimal base

Converts integer input or generates integer output in hexadecimal base

Converts integer input or generates integer output in octal base

Generates floating-point output in fixed-point notation

Generates floating-point output in scientific notation

Skips leading white space before certain input operation.

The following constants are also defined:

left | right | internal

The type iostate is a bitmask type. See Bitmask Types for more information. Setting its elements has the following effects:

Indicates a loss of integrity in an input or output sequence.

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

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

Initial stream state, no other bit is set.

The type openmode is a bitmask type. See Bitmask Types for more information. Setting its elements has the following effects:

Attempts to seek to the end of the file immediately before each write. Each seek and the subsequent write are performed as a single atomic operation.

Attempts to seek to the end of the file immediately after opening. The opening and the subsequent seek may be performed as two operations.

Performs input and output in binary mode rather than text mode. In binary mode the stream treats the contents of the file as a sequence of bytes without interpreting in any special way, certain sequences of characters such as carriage returns and line feeds.

Opens for input.

Opens for output.

Attempts to truncate an existing file to 0 size immediately after opening. The file must be opened for output (i.e., with out ). The opening and the subsequent truncation are performed as a single atomic operation.

Successfully opens the file if and only if a file with that name already exists. The checking for the file’s existence and its subsequent creation are performed as a single atomic operation.

Successfully creates the file if and only if a file with that name does not already exist and the file is being opened for output (i.e., with out ). The checking for the file’s existence and its subsequent creation are performed as a single atomic operation.

The type seekdir is an enumerated type. Setting its elements has the following effects:

Requests a seek relative to the beginning of the stream.

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

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

Constants of the enumerated type event are passed as arguments to user-defined callback functions registered with the stream objects via register_callback() :

The stream object is being erased.

A new locale is being imbued in the stream object.

The copyfmt() member function has been called on an object.

The type event_callback is the type of the callback function used as a parameter in the function register_callback . These functions allow you to use the iword , pword mechanism in an exception-safe environment.

Protected Constructor

The ios_base members have an indeterminate value after construction.

Destructors

Destroys an object of class ios_base . Calls each registered callback pair (fn, index) as (*fn)(erase_event,*this, index) at such a time that any ios_base member function called from within fn has well-defined results.

Public Member Functions

Returns the format control information for both input and output.

Sets flags() to fmtfl and returns the previous value of flags() .

Sets flags() to (fmtfl | flags()) and returns the previous value of flags() .

Clears mask in flags() , sets (fmtfl & mask) in flags() , and returns the previous value of flags() .

Clears mask in flags() .

Returns the imbued locale, which is used to perform locale-dependent input and output operations. The default locale, locale::locale() , is used if no other locale object has been imbued in the stream by a call to the imbue function.

Saves the value returned by getloc() , then assigns loc to a private variable and calls each registered callback pair (fn, index) as (*fn)(imbue_event,*this, index) . It then returns the previously saved value.

If iarray is a null pointer, allocates an array of long s of sufficient size, and stores a pointer to its first element in iarray . The function then extends the array pointed to by iarray , as necessary, to include the element iarray[idx] . Each newly allocated element of the array is initialized to 0 . The reference returned may become invalid after another call to the object’s iword() member with a different index, after a call to its copyfmt() member, or when the object is destroyed. If the function fails, it sets failbit , which may throw an exception. On success, the function returns iarray[idx] ; otherwise, a valid long& initialized to 0 .

Returns the precision (number of digits after the decimal point) to generate on certain output conversions.

Saves the precision, then sets it to prec and returns the previously saved value.

If parray is a null pointer, allocates an array of void* of sufficient size, and stores a pointer to its first element in parray . The function then extends the array pointed at by parray , as necessary, to include the element parray[idx] . Each newly allocated element of the array is initialized to 0 . The reference returned may become invalid after another call to the object’s pword member with a different index, after a call to its copyfmt() member, or when the object is destroyed. If the function fails, it sets failbit , which may throw an exception. On success, the function returns parray[idx] ; otherwise, a valid void*& initialized to 0 .

Registers the pair (fn, index) such that during calls to imbue() , copyfmt() , or

ios_base() , the function fn is called with argument index . Functions registered are called when an event occurs, in opposite order of registration. Functions registered while a callback function is active are not called until the next event. Identical pairs are not merged; a function registered twice is called twice per event.

When called with a false argument, allows the C++ standard streams to operate independently of the standard C streams, which greatly improves performance. When called with a true argument, restores the default synchronization. The return value of the function is the status of the synchronization at the time of the call.

Returns the field width (number of characters) to generate on certain output conversions.

Saves the field width, sets it to wide , and returns the previously saved value.

Returns the next static index that can be used with pword and iword . This is useful if you want to share data between several stream objects.

Class failure

The class failure defines the base class for the types of all objects thrown as exceptions by functions in the iostream s library. It reports errors detected during stream buffer operations.

Constructs an object of class failure , initializing the base class with exception(msg).

Public Member Function

Returns the message msg with which the exception was created.

Class Init

The class Init describes an object whose construction ensures the construction of the eight objects declared in <iostream> , which associates file stream buffers with the standard C streams.

Nonmember Functions

The following functions are ios_base manipulators.

Calls str.setf(ios_base::boolalpha) and returns str .

Calls str.setf(ios_base::dec, ios_base::basefield) and returns str .

Calls str.setf(ios_base::fixed, ios_base::floatfield) and returns str .

Calls str.setf(ios_base::hex, ios_base::basefield) and returns str .

Calls str.setf(ios_base::internal, ios_base::adjustfield) and returns str .

Calls str.setf(ios_base::left, ios_base::adjustfield) and returns str .

Calls str.unsetf(ios_base::boolalpha) and returns str.

Calls str.unsetf(ios_base::showbase) and returns str .

Calls str.unsetf(ios_base::showpoint) and returns str .

Calls str.unsetf(ios_base::showpos) and returns str .

Calls str.unsetf(ios_base::skipws) and returns str .

Calls str.unsetf(ios_base::unitbuf) and returns str .

Calls str.unsetf(ios_base::uppercase) and returns str .

Calls str.setf(ios_base::oct, ios_base::basefield) and returns str .

Calls str.setf(ios_base::right, ios_base::adjustfield) and returns str .

Calls str.setf(ios_base::scientific, ios_base::floatfield) and returns str .

Calls str.setf(ios_base::showbase) and returns str .

Calls str.setf(ios_base::showpoint) and returns s tr .

Calls str.setf(ios_base::showpos) and returns str .

Calls str.setf(ios_base::skipws) and returns str .

Calls str.setf(ios_base::unitbuf) and returns str .

Calls str.setf(ios_base::uppercase) and returns str .

See Also

Standards Conformance

ISO/IEC 14882:1998 — International Standard for Information Systems —Programming Language C++, Section 27.4.2

std:: ios_base

The class ios_base is a multipurpose class that serves as the base class for all I/O stream classes. It maintains several kinds of data:

Typical implementation holds member constants corresponding to all values of fmtflags, iostate, openmode, and seekdir shown below, member variables to maintain current precision, width, and formatting flags, the exception mask, the buffer error state, a resizeable container holding the callbacks, the currently imbued locale, the private storage, and a static integer variable for xalloc().

std::ios_base

Класс ios_base является многоцелевым классом, который служит базовым классом для всех потоковых классов ввода-вывода. Он поддерживает несколько видов данных:

Типичная реализация содержит константы-члены, соответствующие всем значениям fmtflags , iostate , openmode и seekdir , показанные ниже, переменные-члены для поддержания текущей точности, ширины и флагов форматирования, маску исключения, состояние ошибки буфера, изменяемый размер контейнера, содержащий обратные вызовы, текущая введенная локаль, личное хранилище и статическая целочисленная переменная для xalloc() .

std::ios_base — Man Page

Inherited by std::basic_ios< char, _Traits >, std::basic_ios< _CharT, char_traits< _CharT > >, and std::basic_ios< _CharT, _Traits >.

Classes

class failure
These are thrown to indicate problems with io.

Public Types

enum event < erase_event, imbue_event, copyfmt_event >
The set of events that may be passed to an event callback.
typedef void(* event_callback) (event __e, ios_base &__b, int __i)
The type of an event callback function.
typedef _Ios_Fmtflags fmtflags
This is a bitmask type.
typedef _Ios_Iostate iostate
This is a bitmask type.
typedef _Ios_Openmode openmode
This is a bitmask type.
typedef _Ios_Seekdir seekdir
This is an enumerated type.

Public Member Functions

ios_base (const ios_base &)=delete
virtual

ios_base ()
const locale & _M_getloc () const
Locale access.
fmtflags flags () const
Access to format flags.
fmtflags flags (fmtflags __fmtfl)
Setting new format flags all at once.
locale getloc () const
Locale access.
locale imbue (const locale &__loc) throw ()
Setting a new locale.
long & iword (int __ix)
Access to integer array.
ios_base & operator= (const ios_base &)=delete
streamsize precision () const
Flags access.
streamsize precision (streamsize __prec)
Changing flags.
void *& pword (int __ix)
Access to void pointer array.
void register_callback (event_callback __fn, int __index)
Add the callback __fn with parameter __index.
fmtflags setf (fmtflags __fmtfl)
Setting new format flags.
fmtflags setf (fmtflags __fmtfl, fmtflags __mask)
Setting new format flags.
void unsetf (fmtflags __mask)
Clearing format flags.
streamsize width () const
Flags access.
streamsize width (streamsize __wide)
Changing flags.

Static Public Member Functions

static bool sync_with_stdio (bool __sync=true)
Interaction with the standard C I/O objects.
static int xalloc () throw ()
Access to unique indices.

Static Public Attributes

static const openmode __noreplace
static const fmtflags adjustfield
A mask of left|right|internal. Useful for the 2-arg form of setf .
static const openmode app
Seek to end before each write.
static const openmode ate
Open and seek to end immediately after opening.
static const iostate badbit
Indicates a loss of integrity in an input or output sequence (such as an irrecoverable read error from a file).
static const fmtflags basefield
A mask of dec|oct|hex. Useful for the 2-arg form of setf .
static const seekdir beg
Request a seek relative to the beginning of the stream.
static const openmode binary
Perform input and output in binary mode (as opposed to text mode). This is probably not what you think it is; see https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary.
static const fmtflags boolalpha
Insert/extract bool in alphabetic rather than numeric format.
static const seekdir cur
Request a seek relative to the current position within the sequence.
static const fmtflags dec
Converts integer input or generates integer output in decimal base.
static const seekdir end
Request a seek relative to the current end of the sequence.
static const iostate eofbit
Indicates that an input operation reached the end of an input sequence.
static const iostate failbit
Indicates that an input operation failed to read the expected characters, or that an output operation failed to generate the desired characters.
static const fmtflags fixed
Generate floating-point output in fixed-point notation.
static const fmtflags floatfield
A mask of scientific|fixed. Useful for the 2-arg form of setf .
static const iostate goodbit
Indicates all is well.
static const fmtflags hex
Converts integer input or generates integer output in hexadecimal base.
static const openmode in
Open for input. Default for ifstream and fstream.
static const fmtflags internal
Adds fill characters at a designated internal point in certain generated output, or identical to right if no such point is designated.
static const fmtflags left
Adds fill characters on the right (final positions) of certain generated output. (I.e., the thing you print is flush left.)
static const fmtflags oct
Converts integer input or generates integer output in octal base.
static const openmode out
Open for output. Default for ofstream and fstream.
static const fmtflags right
Adds fill characters on the left (initial positions) of certain generated output. (I.e., the thing you print is flush right.)
static const fmtflags scientific
Generates floating-point output in scientific notation.
static const fmtflags showbase
Generates a prefix indicating the numeric base of generated integer output.
static const fmtflags showpoint
Generates a decimal-point character unconditionally in generated floating-point output.
static const fmtflags showpos
Generates a + sign in non-negative generated numeric output.
static const fmtflags skipws
Skips leading white space before certain input operations.
static const openmode trunc
Truncate an existing stream when opening. Default for ofstream .
static const fmtflags unitbuf
Flushes output after each output operation.
static const fmtflags uppercase
Replaces certain lowercase letters with their uppercase equivalents in generated output.

Protected Types

Protected Member Functions

void _M_call_callbacks (event __ev) throw ()
void _M_dispose_callbacks (void) throw ()
_Words & _M_grow_words (int __index, bool __iword)
void _M_init () throw ()
void _M_move (ios_base &) noexcept
void _M_swap (ios_base &__rhs) noexcept

Protected Attributes

_Callback_list * _M_callbacks
iostate _M_exception
fmtflags _M_flags
locale _M_ios_locale
_Words _M_local_word [_S_local_word_size]
streamsize _M_precision
iostate _M_streambuf_state
streamsize _M_width
_Words * _M_word
int _M_word_size
_Words _M_word_zero

Detailed Description

The base of the I/O class hierarchy.

This class defines everything that can be defined about I/O that does not depend on the type of characters being input or output. Most people will only see ios_base when they need to specify the full name of the various I/O flags (e.g., the openmodes).

Member Typedef Documentation

typedef void(* std::ios_base::event_callback) (event __e, ios_base &__b, int __i)

The type of an event callback function.

Parameters

__e One of the members of the event enum.
__b Reference to the ios_base object.
__i 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

typedef _Ios_Fmtflags std::ios_base::fmtflags

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

typedef _Ios_Iostate std::ios_base::iostate

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

typedef _Ios_Openmode std::ios_base::openmode

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

typedef _Ios_Seekdir std::ios_base::seekdir

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.

Member Enumeration Documentation

enum std::ios_base::event

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().

Constructor & Destructor Documentation

virtual std::ios_base::

Invokes each callback with erase_event. Destroys local storage.

Note that the ios_base object for the standard streams never gets destroyed. As a result, any callbacks registered with the standard streams will not get invoked with erase_event (unless copyfmt is used).

Member Function Documentation

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

Returns

A reference to the current locale.

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

Referenced by std::money_get< _CharT, _InIter >::do_get(), std::time_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::num_put< _CharT, _OutIter >::do_put(), std::time_put< _CharT, _OutIter >::do_put(), std::time_get< _CharT, _InIter >::get(), and std::time_put< _CharT, _OutIter >::put().

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

Access to format flags.

Returns

The format control flags for both input and output.

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::basic_ios< _CharT, _Traits >::copyfmt(), std::num_get< _CharT, _InIter >::do_get(), std::num_put< _CharT, _OutIter >::do_put(), std::normal_distribution< double >::operator()(), std::operator<<(), std::chrono::operator<<(), std::operator>>(), and std::__detail::operator>>().

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

Setting new format flags all at once.

Parameters

__fmtfl The new flags to set.

The previous format control flags.

This function overwrites all the format flags with __fmtfl.

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

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.

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

locale std::ios_base::imbue (const locale & __loc)

Setting a new locale.

Parameters

__loc The new locale.

The previous locale.

Sets the new locale for this stream, and then invokes each callback with imbue_event.

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

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

Access to integer array.

Parameters

__ix Index into the array.

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.

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

Returns

The precision to generate on certain output operations.

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

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

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

Parameters

__prec The new precision value.

The previous value of precision().

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

Access to void pointer array.

Parameters

__ix Index into the array.

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.

void std::ios_base::register_callback (event_callback __fn, int __index)

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.

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

Setting new format flags.

Parameters

__fmtfl Additional flags to set.

The previous format control flags.

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

Referenced by std::__detail::operator>>().

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

Setting new format flags.

Parameters

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

The previous format control flags.

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

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

Interaction with the standard C I/O objects.

Parameters

__sync Whether to synchronize or not.

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 https://gcc.gnu.org/onlinedocs/libstdc++/manual/fstreams.html#std.io.filestreams.binary

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

Clearing format flags.

Parameters

__mask The flags to unset.

This function clears __mask in the format flags.

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

Returns

The minimum field width to generate on output operations.

Minimum field width refers to the number of characters.

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

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

Parameters

__wide The new width value.

The previous value of width().

static int std::ios_base::xalloc () [static]

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

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

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

Referenced by std::num_put< _CharT, _OutIter >::do_put(), std::internal(), std::left(), and std::right().

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

Seek to end before each write.

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

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

Open and seek to end immediately after opening.

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

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

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

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::basic_ios< _CharT, _Traits >::bad(), std::basic_ios< _CharT, _Traits >::fail(), std::basic_ostream< _CharT, _Traits >::flush(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< char >::get(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_ostream< _CharT, _Traits >::put(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::readsome(), std::basic_istream< char >::seekg(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::sync(), std::basic_istream< char >::tellg(), std::basic_istream< _CharT, _Traits >::tellg(), and std::ws().

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

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

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

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

Request a seek relative to the beginning of the stream.

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

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

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

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

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

Insert/extract bool in alphabetic rather than numeric format.

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

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

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

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

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

Converts integer input or generates integer output in decimal base.

Referenced by std::dec().

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

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

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

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

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

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::time_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::basic_ios< _CharT, _Traits >::eof(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< char >::get(), std::time_get< _CharT, _InIter >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_istream< _CharT, _Traits >::operator>>(), std::operator>>(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::readsome(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< char >::sync(), std::basic_istream< _CharT, _Traits >::unget(), and std::ws().

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

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

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::basic_ostream< _CharT, _Traits >::sentry::sentry(), std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::time_get< _CharT, _InIter >::do_get_weekday(), std::time_get< _CharT, _InIter >::do_get_year(), std::basic_ios< _CharT, _Traits >::fail(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< char >::get(), std::time_get< _CharT, _InIter >::get(), std::operator>>(), std::basic_istream< _CharT, _Traits >::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]

Generate floating-point output in fixed-point notation.

Referenced by std::fixed(), and std::hexfloat().

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

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

Referenced by std::defaultfloat(), std::fixed(), std::hexfloat(), and std::scientific().

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

Indicates all is well.

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::time_get< _CharT, _InIter >::do_get(), std::num_get< _CharT, _InIter >::do_get(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::time_get< _CharT, _InIter >::do_get_weekday(), std::time_get< _CharT, _InIter >::do_get_year(), std::basic_ostream< _CharT, _Traits >::flush(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< char >::get(), std::time_get< _CharT, _InIter >::get(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_ostream< _CharT, _Traits >::put(), std::basic_istream< _CharT, _Traits >::putback(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< char >::readsome(), std::basic_istream< _CharT, _Traits >::readsome(), std::basic_istream< _CharT, _Traits >::seekg(), std::basic_istream< _CharT, _Traits >::sync(), std::basic_istream< _CharT, _Traits >::unget(), and std::ws().

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

Converts integer input or generates integer output in hexadecimal base.

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

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

Open for input. Default for ifstream and fstream.

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

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

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

Referenced by std::internal().

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

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

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

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

Converts integer input or generates integer output in octal base.

Referenced by std::oct().

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

Open for output. Default for ofstream and fstream.

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

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

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

Referenced by std::right().

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

Generates floating-point output in scientific notation.

Referenced by std::hexfloat(), and std::scientific().

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

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

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

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

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

Referenced by std::noshowpoint(), and std::showpoint().

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

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

Referenced by std::noshowpos(), and std::showpos().

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

Skips leading white space before certain input operations.

Referenced by std::basic_istream< _CharT, _Traits >::sentry::sentry(), std::noskipws(), std::__detail::operator>>(), and std::skipws().

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

Truncate an existing stream when opening. Default for ofstream .

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

Flushes output after each output operation.

Referenced by std::nounitbuf(), and std::unitbuf().

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

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

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

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