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basic_ios Class

The template class describes the storage and member functions common to both input streams (of template class basic_istream) and output streams (of template class basic_ostream) that depend on the template parameters. (The class ios_base describes what is common and not dependent on template parameters.) An object of class basic_ios<class Elem, class Traits> helps control a stream with elements of type Elem, whose character traits are determined by the class Traits.

template <class Elem, class Traits> 
   class basic_ios : public ios_base

Parameters

  • Elem
    A type.

  • Traits
    A variable of type char_traits.

Remarks

An object of class basic_ios<class Elem, class Traits> stores:

Constructors

basic_ios

Constructs the basic_ios class.

Typedefs

char_type

A synonym for the template parameter Elem.

int_type

A synonym for Traits::int_type.

off_type

A synonym for Traits::off_type.

pos_type

A synonym for Traits::pos_type.

traits_type

A synonym for the template parameter Traits.

Member Functions

bad

Indicates a loss of integrity of the stream buffer.

clear

Clears all error flags.

copyfmt

Copies flags from one stream to another.

eof

Indicates if the end of a stream has been reached.

exceptions

Indicates which exceptions will be thrown by the stream.

fail

Indicates failure to extract a valid field from a stream.

fill

Specifies or returns the character that will be used when the text is not as wide as the stream.

good

Indicates the stream is in good condition.

imbue

Changes the locale.

init

Called by basic_ios constructors.

move

Moves all values, except the pointer to the stream buffer, from the parameter to the current object.

narrow

Finds the equivalent char to a given char_type.

rdbuf

Routes stream to specified buffer.

rdstate

Reads the state of bits for flags.

set_rdbuf

Assigns a stream buffer to be the read buffer for this stream object.

setstate

Sets additional flags.

swap

Exchanges the values in this basic_ios object for those of another basic_ios object. The pointers to the stream buffers are not swapped.

tie

Ensures that one stream is processed before another stream.

widen

Finds the equivalent char_type to a given char.

Operators

explicit operator bool

Allows use of a basic_ios object as a bool. Automatic type conversion is disabled to prevent common, unintended side effects.

operator void *

Indicates if the stream is still good.

operator!

Indicates if the stream is not bad.

Requirements

Header: <ios>

Namespace: std

See Also

Reference

Thread Safety in the C++ Standard Library

iostream Programming

iostreams Conventions