std::ios_base

std::ios_base Class Reference

The very top of the I/O class hierarchy. More...

#include <ios_base.h>

Inheritance diagram for std::ios_base:

[legend]
List of all members.

Public Types

typedef IosFmtflags fmtflags
 This is a bitmask type.
typedef IosIostate iostate
 This is a bitmask type.
typedef IosOpenmode openmode
 This is a bitmask type.
typedef IosSeekdir seekdir
 This is an enumerated type.
typedef void(* event_callback )(event, ios_base &, int)
enum  event

Public Member Functions

void register_callback (event_callback __fn, int index)
fmtflags flags () const
 Access to format flags.
fmtflags flags (fmtflags __fmtfl)
 Setting new format flags all at once.
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 precision () const
 Flags access.
streamsize precision (streamsize __prec)
 Changing flags.
streamsize width () const
 Flags access.
streamsize width (streamsize __wide)
 Changing flags.
locale imbue (const locale &__loc)
 Setting a new locale.
locale getloc () const
 Locale access.
const locale & M_getloc () const
 Locale access.
long & iword (int __ix)
void *& pword (int __ix)
 ~ios_base ()

Static Public Member Functions

static bool sync_with_stdio (bool sync=true)
 Interaction with the standard C I/O objects.
static int xalloc () throw ()

Static Public Attributes

static const fmtflags boolalpha
 Insert/extract bool in alphabetic rather than numeric format.
static const fmtflags dec
 Converts integer input or generates integer output in decimal base.
static const fmtflags fixed
 Generate floating-point output in fixed-point notation.
static const fmtflags hex
 Converts integer input or generates integer output in hexadecimal base.
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 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 fmtflags unitbuf
 Flushes output after each output operation.
static const fmtflags uppercase
 Replaces certain lowercase letters with their uppercase equivalents in generated output.
static const fmtflags adjustfield
 A mask of left|right|internal. Useful for the 2-arg form of setf.
static const fmtflags basefield
 A mask of dec|oct|hex. Useful for the 2-arg form of setf.
static const fmtflags floatfield
 A mask of scientific|fixed. Useful for the 2-arg form of setf.
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 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 iostate goodbit
 Indicates all is well.
static const openmode app
 Seek to end before each write.
static const openmode ate
 Open and seek to end immediately after opening.
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 http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#3 and http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#7 for more.
static const openmode in
 Open for input. Default for ifstream and fstream.
static const openmode out
 Open for output. Default for ofstream and fstream.
static const openmode trunc
 Open for input. Default for ofstream.
static const seekdir beg
 Request a seek relative to the beginning of the stream.
static const seekdir cur
 Request a seek relative to the current position within the sequence.
static const seekdir end
 Request a seek relative to the current end of the sequence.

Classes

class  failure
 These are thrown to indicate problems. Doc me. More...

Detailed Description

The very top 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 158 of file ios_base.h.

Member Typedef Documentation

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

Todo:
Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 355 of file ios_base.h.

typedef IosFmtflags std::ios_base::fmtflags
 

This is a bitmask type.

"IosFmtflags" 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 212 of file ios_base.h.

typedef IosIostate std::ios_base::iostate
 

This is a bitmask type.

"IosIostate" 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 269 of file ios_base.h.

typedef IosOpenmode std::ios_base::openmode
 

This is a bitmask type.

"IosOpenmode" 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 296 of file ios_base.h.

typedef IosSeekdir std::ios_base::seekdir
 

This is an enumerated type.

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

  • beg
  • cur, equivalent to SEEKCUR in the C standard library.
  • end, equivalent to SEEKEND in the C standard library.

Definition at line 323 of file ios_base.h.

Member Enumeration Documentation

enum std::ios_base::event
 

Todo:
Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 345 of file ios_base.h.

Constructor & Destructor Documentation

std::ios_base::~ios_base (   ) 
 

Destroys local storage and [XXX does something with callbacks].

Definition at line 321 of file ios.cc.

Member Function Documentation

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 482 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 472 of file ios_base.h.

Referenced by std::basic_ios< CharT, Traits >::copyfmt(), std::basic_ostream< CharT, Traits >::operator<<(), and std::basic_ostream< char >::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 614 of file ios_base.h.

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 [XXX does something with callbacks].

Reimplemented in std::basic_ios< CharT, Traits >, and std::basic_ios< char, Traits >.

Definition at line 304 of file ios.cc.

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

Todo:
Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 637 of file ios_base.h.

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 624 of file ios_base.h.

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 550 of file ios_base.h.

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

Flags access.

Returns:
The precision to generate on certain output operations.

Definition at line 542 of file ios_base.h.

Referenced by std::basic_ios< CharT, Traits >::copyfmt().

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

Todo:
Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 648 of file ios_base.h.

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

Todo:
Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 333 of file ios.cc.

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 515 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 498 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().

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.

Definition at line 364 of file ios.cc.

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 530 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 572 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 564 of file ios_base.h.

Referenced by std::basic_ios< CharT, Traits >::copyfmt(), and std::operator<<().

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

Todo:
Doc me! See docs/doxygen/TODO and http://gcc.gnu.org/ml/libstdc++/2002-02/msg00003.html for more.

Definition at line 241 of file ios.cc.

Member Data Documentation

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

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

Definition at line 122 of file ios.cc.

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

Seek to end before each write.

Definition at line 131 of file ios.cc.

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

Open and seek to end immediately after opening.

Definition at line 132 of file ios.cc.

const ios_base::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).

Definition at line 126 of file ios.cc.

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

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

Definition at line 123 of file ios.cc.

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

Request a seek relative to the beginning of the stream.

Definition at line 138 of file ios.cc.

const ios_base::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 http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#3 and http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#7 for more.

Definition at line 133 of file ios.cc.

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

Insert/extract bool in alphabetic rather than numeric format.

Definition at line 107 of file ios.cc.

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

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

Definition at line 139 of file ios.cc.

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

Converts integer input or generates integer output in decimal base.

Definition at line 108 of file ios.cc.

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

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

Definition at line 140 of file ios.cc.

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

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

Definition at line 127 of file ios.cc.

const ios_base::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.

Definition at line 128 of file ios.cc.

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

Generate floating-point output in fixed-point notation.

Definition at line 109 of file ios.cc.

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

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

Definition at line 124 of file ios.cc.

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

Indicates all is well.

Definition at line 129 of file ios.cc.

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

Converts integer input or generates integer output in hexadecimal base.

Definition at line 110 of file ios.cc.

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

Open for input. Default for ifstream and fstream.

Definition at line 134 of file ios.cc.

const ios_base::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.

Definition at line 111 of file ios.cc.

const ios_base::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.).

Definition at line 112 of file ios.cc.

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

Converts integer input or generates integer output in octal base.

Definition at line 113 of file ios.cc.

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

Open for output. Default for ofstream and fstream.

Definition at line 135 of file ios.cc.

const ios_base::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.).

Definition at line 114 of file ios.cc.

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

Generates floating-point output in scientific notation.

Definition at line 115 of file ios.cc.

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

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

Definition at line 116 of file ios.cc.

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

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

Definition at line 117 of file ios.cc.

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

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

Definition at line 118 of file ios.cc.

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

Skips leading white space before certain input operations.

Definition at line 119 of file ios.cc.

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

Open for input. Default for ofstream.

Definition at line 136 of file ios.cc.

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

Flushes output after each output operation.

Definition at line 120 of file ios.cc.

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

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

Definition at line 121 of file ios.cc.

The documentation for this class was generated from the following files:
Generated on Sat Mar 19 18:32:32 2005 for libstdc++-v3 Source by  doxygen 1.4.1