std::ios_base Class Reference

Inheritance diagram for std::ios_base:

Inheritance graph
List of all members.

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).

Definition at line 203 of file ios_base.h.

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Types

Protected Member Functions

Protected Attributes

Classes


Member Typedef Documentation

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

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().

Definition at line 437 of file ios_base.h.

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:

Definition at line 255 of file ios_base.h.

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:

Definition at line 330 of file ios_base.h.

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:

Definition at line 361 of file ios_base.h.

typedef _Ios_Seekdir std::ios_base::seekdir

This is an enumerated type.

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

Definition at line 394 of file ios_base.h.


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().

Definition at line 420 of file ios_base.h.


Constructor & Destructor Documentation

virtual std::ios_base::~ios_base (  )  [virtual]

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]

Locale access.

Returns:
A reference to the current locale.
Like getloc above, but returns a reference instead of generating a copy.

Definition at line 703 of file ios_base.h.

Referenced by std::money_get< _CharT, _InIter >::_M_extract(), std::num_get< _CharT, _InIter >::_M_extract_float(), std::num_get< _CharT, _InIter >::_M_extract_int(), std::time_get< _CharT, _InIter >::_M_extract_name(), std::time_get< _CharT, _InIter >::_M_extract_num(), std::time_get< _CharT, _InIter >::_M_extract_via_format(), std::money_put< _CharT, _OutIter >::_M_insert(), std::num_put< _CharT, _OutIter >::_M_insert_float(), std::num_put< _CharT, _OutIter >::_M_insert_int(), std::__pad< _CharT, _Traits >::_S_pad(), 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().

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

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 559 of file ios_base.h.

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

Access to format flags.

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

Definition at line 548 of file ios_base.h.

Referenced by std::__ostream_insert(), std::money_get< _CharT, _InIter >::_M_extract(), std::num_get< _CharT, _InIter >::_M_extract_int(), std::money_put< _CharT, _OutIter >::_M_insert(), std::num_put< _CharT, _OutIter >::_M_insert_float(), std::num_put< _CharT, _OutIter >::_M_insert_int(), std::__pad< _CharT, _Traits >::_S_pad(), std::basic_ios< _CharT, _Traits >::copyfmt(), std::num_get< _CharT, _InIter >::do_get(), std::num_put< _CharT, _OutIter >::do_put(), __gnu_cxx::operator<<(), std::operator<<(), std::basic_ostream< _CharT, _Traits >::operator<<(), and std::operator>>().

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

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 692 of file ios_base.h.

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

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

Setting a new locale.

Parameters:
loc The new locale.
Returns:
The previous locale.
Sets the new locale for this stream, and then invokes each callback with imbue_event.

Reimplemented in std::basic_ios< _CharT, _Traits >, and std::basic_ios< char, _Traits >.

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.
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 738 of file ios_base.h.

References std::ios_base::_Words::_M_iword.

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

Changing flags.

Parameters:
prec The new precision value.
Returns:
The previous value of precision().

Definition at line 627 of file ios_base.h.

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

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 618 of file ios_base.h.

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

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

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 759 of file ios_base.h.

References std::ios_base::_Words::_M_pword.

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,
fmtflags  __mask 
) [inline]

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 592 of file ios_base.h.

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

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 575 of file ios_base.h.

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

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.
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++/27_io/howto.html#8 for more.

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.

Definition at line 607 of file ios_base.h.

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

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

Changing flags.

Parameters:
wide The new width value.
Returns:
The previous value of width().

Definition at line 650 of file ios_base.h.

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

Flags access.

Returns:
The minimum field width to generate on output operations.
"Minimum field width" refers to the number of characters.

Definition at line 641 of file ios_base.h.

Referenced by std::__ostream_insert(), std::money_put< _CharT, _OutIter >::_M_insert(), std::num_put< _CharT, _OutIter >::_M_insert_float(), std::num_put< _CharT, _OutIter >::_M_insert_int(), std::basic_ios< _CharT, _Traits >::copyfmt(), std::num_put< _CharT, _OutIter >::do_put(), __gnu_cxx::operator<<(), std::operator<<(), and std::operator>>().

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

streamsize std::ios_base::_M_precision [protected]

ios_base data members (doc me)

Definition at line 457 of file ios_base.h.

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

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

Definition at line 310 of file ios_base.h.

Referenced by std::money_put< _CharT, _OutIter >::_M_insert(), and std::__pad< _CharT, _Traits >::_S_pad().

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

Seek to end before each write.

Definition at line 364 of file ios_base.h.

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

Open and seek to end immediately after opening.

Definition at line 367 of file ios_base.h.

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

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

as an irrecoverable read error from a file).

Definition at line 334 of file ios_base.h.

Referenced by std::basic_istream< _CharT, _Traits >::_M_extract(), std::basic_ostream< _CharT, _Traits >::_M_insert(), std::basic_ostream< _CharT, _Traits >::flush(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::getline(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_ios< _CharT, _Traits >::init(), std::operator<<(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::operator>>(), std::basic_istream< _CharT, _Traits >::peek(), 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< _CharT, _Traits >::seekg(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_istream< _CharT, _Traits >::sync(), std::basic_istream< _CharT, _Traits >::tellg(), std::basic_ostream< _CharT, _Traits >::tellp(), std::basic_istream< _CharT, _Traits >::unget(), and std::basic_ostream< _CharT, _Traits >::write().

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

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

Definition at line 313 of file ios_base.h.

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

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

Request a seek relative to the beginning of the stream.

Definition at line 397 of file ios_base.h.

Referenced by __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >::seekoff(), __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >::seekpos(), and std::basic_filebuf< _CharT, _Traits >::seekpos().

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

http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#7 for more.

Definition at line 373 of file ios_base.h.

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

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

Insert/extract bool in alphabetic rather than numeric format.

Definition at line 258 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]

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

Definition at line 400 of file ios_base.h.

Referenced by std::basic_filebuf< _CharT, _Traits >::imbue(), std::basic_filebuf< _CharT, _Traits >::pbackfail(), __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_filebuf< _CharT, _Traits >::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.

Definition at line 261 of file ios_base.h.

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

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

Definition at line 403 of file ios_base.h.

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.

Definition at line 337 of file ios_base.h.

Referenced by std::money_get< _CharT, _InIter >::_M_extract(), std::num_get< _CharT, _InIter >::_M_extract_float(), std::num_get< _CharT, _InIter >::_M_extract_int(), 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_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::getline(), std::basic_istream< _CharT, _Traits >::ignore(), std::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_istream< _CharT, _Traits >::peek(), std::basic_istream< _CharT, _Traits >::read(), std::basic_istream< _CharT, _Traits >::readsome(), and std::ws().

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

desired characters.

Definition at line 342 of file ios_base.h.

Referenced by std::money_get< _CharT, _InIter >::_M_extract(), std::num_get< _CharT, _InIter >::_M_extract_float(), std::num_get< _CharT, _InIter >::_M_extract_int(), std::time_get< _CharT, _InIter >::_M_extract_name(), std::time_get< _CharT, _InIter >::_M_extract_num(), std::time_get< _CharT, _InIter >::_M_extract_via_format(), 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_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::getline(), std::basic_ostream< _CharT, _Traits >::operator<<(), 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.

Definition at line 264 of file ios_base.h.

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

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

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

Definition at line 316 of file ios_base.h.

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

Indicates all is well.

Definition at line 345 of file ios_base.h.

Referenced by std::basic_istream< _CharT, _Traits >::_M_extract(), std::time_get< _CharT, _InIter >::_M_extract_via_format(), std::basic_ostream< _CharT, _Traits >::_M_insert(), std::time_get< _CharT, _InIter >::do_get_monthname(), std::time_get< _CharT, _InIter >::do_get_weekday(), std::basic_ostream< _CharT, _Traits >::flush(), std::basic_istream< _CharT, _Traits >::get(), std::basic_istream< _CharT, _Traits >::getline(), std::basic_istream< _CharT, _Traits >::ignore(), std::basic_ios< _CharT, _Traits >::init(), std::basic_ostream< _CharT, _Traits >::operator<<(), std::operator>>(), std::basic_istream< _CharT, _Traits >::operator>>(), std::basic_istream< _CharT, _Traits >::peek(), 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< _CharT, _Traits >::seekg(), std::basic_ostream< _CharT, _Traits >::seekp(), std::basic_istream< _CharT, _Traits >::sync(), and std::basic_istream< _CharT, _Traits >::unget().

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

Converts integer input or generates integer output in hexadecimal base.

Definition at line 267 of file ios_base.h.

Referenced by std::num_get< _CharT, _InIter >::_M_extract_int(), std::num_put< _CharT, _OutIter >::_M_insert_int(), 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]

Open for input. Default for ifstream and fstream.

Definition at line 376 of file ios_base.h.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::_M_sync(), 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_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]

designated.

Definition at line 272 of file ios_base.h.

Referenced by std::money_put< _CharT, _OutIter >::_M_insert(), std::__pad< _CharT, _Traits >::_S_pad(), and std::num_put< _CharT, _OutIter >::do_put().

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

generated output. (I.e., the thing you print is flush left.)

Definition at line 276 of file ios_base.h.

Referenced by std::money_put< _CharT, _OutIter >::_M_insert(), std::__pad< _CharT, _Traits >::_S_pad(), and __gnu_cxx::operator<<().

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

Converts integer input or generates integer output in octal base.

Definition at line 279 of file ios_base.h.

Referenced by std::__int_to_char(), std::num_get< _CharT, _InIter >::_M_extract_int(), std::num_put< _CharT, _OutIter >::_M_insert_int(), and std::basic_ostream< _CharT, _Traits >::operator<<().

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

Open for output. Default for ofstream and fstream.

Definition at line 379 of file ios_base.h.

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

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

generated output. (I.e., the thing you print is flush right.)

Definition at line 283 of file ios_base.h.

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

Generates floating-point output in scientific notation.

Definition at line 286 of file ios_base.h.

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

output.

Definition at line 290 of file ios_base.h.

Referenced by std::money_get< _CharT, _InIter >::_M_extract(), std::money_put< _CharT, _OutIter >::_M_insert(), std::num_put< _CharT, _OutIter >::_M_insert_int(), and std::num_put< _CharT, _OutIter >::do_put().

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

floating-point output.

Definition at line 294 of file ios_base.h.

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

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

Definition at line 297 of file ios_base.h.

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

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

Skips leading white space before certain input operations.

Definition at line 300 of file ios_base.h.

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

Open for input. Default for ofstream.

Definition at line 382 of file ios_base.h.

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

Flushes output after each output operation.

Definition at line 303 of file ios_base.h.

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

in generated output.

Definition at line 307 of file ios_base.h.

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


The documentation for this class was generated from the following file:
Generated on Wed Mar 26 00:44:37 2008 for libstdc++ by  doxygen 1.5.1