C++ Library -

Introduction

The C++ standard libraries provide an extensive set of input/output capabilities which we will see in subsequent chapters. This chapter will discuss very basic and most common I/O operations required for C++ programming.
Input-Output base classes and types for the IOStream hierarchy of classes as shown below −

Types

Class templates

S.N.	Member types	Definition
1	basic_ios	Base class for streams (type-dependent components
2	fpos	Stream position class template

Classes

S.N.	Member types	Definition
1	ios	Base class for streams (type-dependent components)
2	ios_base	Base class for streams
3	wios	Base class for wide character streams

Other types

S.N.	Member types	Definition
1	io_errc	Input/output error conditions
2	streamoff	Stream offset type
3	streampos	Stream position type
4	streamsize	Stream size type
5	wstreampos	Wide stream position type

Format flag manipulators (functions)

Independent flags (switch on) −

S.N.	Member types	Definition
1	boolalpha	Alphanumerical bool values
2	showbase	Show numerical base prefixes
3	showpoint	Show decimal point
4	showpos	Show positive signs
5	skipws	Skip whitespaces
6	unitbuf	Flush buffer after insertions
7	uppercase	Generate upper-case letters

Independent flags (switch off) −

S.N.	Member types	Definition
1	noboolalpha	No alphanumerical bool values
2	noshowbase	Do not show numerical base prefixes
3	noshowpoint	Do not show decimal point
4	noshowpos	Do not show positive signs
5	noskipws	Do not skip whitespaces
6	nounitbuf	Do not force flushes after insertions
7	nouppercase	Do not generate upper case letters

Numerical base format flags ("basefield" flags) −

S.N.	Member types	Definition
1	dec	Use decimal base
2	hex	Use hexadecimal base
3	oct	Use octal base

Floating-point format flags ("floatfield" flags) −

S.N.	Member types	Definition
1	fixed	Use fixed floating-point notation
2	scientific	Use scientific floating-point notation

Adustment format flags ("adjustfield" flags) −

S.N.	Member types	Definition
1	internal	Adjust field by inserting characters at an internal position
2	left	Adjust output to the left
3	right	Adjust output to the right