ios

#include <iostream.h>

As the iostream class hierarchy diagram shows, ios is the base class for all the input/output stream classes. While ios is not technically an abstract base class, you will not usually construct ios objects, nor will you derive classes directly from ios. Instead, you will use the derived classes istream and ostream or other derived classes.

Even though you will not use ios directly, you will be using many of the inherited member functions and data members described here. Remember that these inherited member function descriptions are not duplicated for derived classes.

Data Members (static) — Public Members

basefield

Mask for obtaining the conversion base flags (dec, oct, or hex).

adjustfield

Mask for obtaining the field padding flags (left, right, or internal).

floatfield

Mask for obtaining the numeric format (scientific or fixed).

Construction/Destruction — Public Members

ios

Constructor for use in derived classes.

~ios

Virtual destructor.

Flag and Format Access Functions — Public Members

flags

Sets or reads the stream’s format flags.

setf

Manipulates the stream’s format flags.

unsetf

Clears the stream’s format flags.

fill

Sets or reads the stream’s fill character.

precision

Sets or reads the stream’s floating-point format display precision.

width

Sets or reads the stream’s output field width.

Status-Testing Functions — Public Members

good

Indicates good stream status.

bad

Indicates a serious I/O error.

eof

Indicates end of file.

fail

Indicates a serious I/O error or a possibly recoverable I/O formatting error.

rdstate

Returns the stream’s error flags.

clear

Sets or clears the stream’s error flags.

User-Defined Format Flags — Public Members

bitalloc

Provides a mask for an unused format bit in the stream’s private flags variable (static function).

xalloc

Provides an index to an unused word in an array reserved for special-purpose stream state variables (static function).

iword

Converts the index provided by xalloc to a reference (valid only until the next xalloc).

pword

Converts the index provided by xalloc to a pointer (valid only until the next xalloc).

Other Functions — Public Members

delbuf

Controls the connection of streambuf deletion with ios destruction.

rdbuf

Gets the stream’s streambuf object.

sync_with_stdio

Synchronizes the predefined objects cin, cout, cerr, and clog with the standard I/O system.

tie

Ties a specified ostream to this stream.

Operators — Public Members

operator void*

Converts a stream to a pointer that can be used only for error checking.

operator !

Returns a nonzero value if a stream I/O error occurs.

ios Manipulators

dec

Causes the interpretation of subsequent fields in decimal format (the default mode).

hex

Causes the interpretation of subsequent fields in hexadecimal format.

oct

Causes the interpretation of subsequent fields in octal format.

binary

Sets the stream’s mode to binary (stream must have an associated filebuf buffer).

text

Sets the stream’s mode to text,  the default mode (stream must have an associated filebuf buffer).

Parameterized Manipulators

(#include <iomanip.h> required)

setiosflags

Sets the stream’s format flags.

resetiosflags

Resets the stream’s format flags.

setfill

Sets the stream’s fill character.

setprecision

Sets the stream’s floating-point display precision.

setw

Sets the stream’s field width (for the next field only).

Abstract Stream Base Class

See Also   istream, ostream