The class OutputStream corresponds, essentially, to the class ostream from the C++ IO-Stream library. More...

#include <object/outputstream.h>

Inheritance diagram for OutputStream:

Collaboration diagram for OutputStream:

Public Member Functions
	OutputStream ()
	Default constructor. Initial number system is decimal.

virtual	~OutputStream ()
	Destructor.

virtual void	flush ()=0
	Clears the buffer. More...

OutputStream &	operator<< (char c)
	Print a single character. More...

OutputStream &	operator<< (unsigned char c)
	Print a single character. More...

OutputStream &	operator<< (const char *string)
	Printing a null-terminated string. More...

OutputStream &	operator<< (bool b)
	Print a boolean value. More...

OutputStream &	operator<< (short ival)
	Print an integral number in radix `base` More...

OutputStream &	operator<< (unsigned short ival)
	Print an integral number in radix `base` More...

OutputStream &	operator<< (int ival)
	Print an integral number in radix `base` More...

OutputStream &	operator<< (unsigned int ival)
	Print an integral number in radix `base` More...

OutputStream &	operator<< (long ival)
	Print an integral number in radix `base` More...

OutputStream &	operator<< (unsigned long ival)
	Print an integral number in radix `base` More...

OutputStream &	operator<< (long long ival)
	Print an integral number in radix `base` More...

OutputStream &	operator<< (unsigned long long ival)
	Print an integral number in radix `base` More...

OutputStream &	operator<< (const void *ptr)
	Print a pointer as hexadecimal number. More...

OutputStream &	operator<< (OutputStream &(*f)(OutputStream &))
	Calls one of the manipulator functions. More...

Public Member Functions inherited from Stringbuffer
virtual	~Stringbuffer ()
	Destructor (nothing to do here)

Public Attributes
int	base
	Number system used for printing integral numbers (one of 2, 8, 10, or 16)

Additional Inherited Members
Protected Member Functions inherited from Stringbuffer
	Stringbuffer ()
	Constructor; Marks the buffer as empty.

void	put (char c)
	Inserts a character into the buffer. More...

virtual void	flush ()=0
	Flush the buffer contents. More...

Protected Attributes inherited from Stringbuffer
char	buffer [80]
	buffer containing characters that will be printed upon flush()

long unsigned	pos
	current position in the buffer

Detailed Description

The class OutputStream corresponds, essentially, to the class ostream from the C++ IO-Stream library.

As relying on the method Stringbuffer::put() is quite cumbersome when not only printing single characters, but numbers and whole strings, the class OutputStream provides a convenient way of composing output of variables of varying data types. Therefore, OutputStream implements shift operators operator<<` for various data types (similar to those known from the C++ IO-Stream library)

For further convenience, OutputStream also allows printing integral numbers in decimal, binary, octal, and hexadecimal format. Remember that, for negative numbers, the sign is only printed when using the decimal number system; for binary, octal, and hex, the number is printed as stored in the machine word without interpreting the sign. For Intel CPUs, two's complement is used for storing negative values, -1, for example, will print hex FFFFFFFF and octal 37777777777.

OutputStream's public methods/operators all return a reference to the object they are called on (i.e. *this). Returning *this allows chaining those stream operators in a single expression, such as kout << "a = " << a;

At this point in time, OutputStream implements operator<< for chars, strings and whole numbers. An additional operator<< allows using manipulators whose detailed description is given below.

Member Function Documentation

◆ flush()

virtual void OutputStream::flush ( )

pure virtual

Clears the buffer.

Pure virtual method that must be implemented by derived (non-abstract) classes. Formatting of the buffer contents can be implemented differently by different derived classes

Implements Stringbuffer.

Implemented in TextStream, ConsoleOut, and FileOut.

◆ operator<<() [1/14]

OutputStream & OutputStream::operator<< ( char c )

Print a single character.

Parameters

c	Character to be printed

Returns: Reference to OutputStream os; allows operator chaining.

◆ operator<<() [2/14]

OutputStream & OutputStream::operator<< ( unsigned char c )

Print a single character.

Note: In C, there are no "characters" in that sense, but only integers. A char, therefore, is a 8 bit number with the most significant bit (optionally) representing a sign. Depending on whether signed or not, the value ranges are [-128, 127] or [0; 255]. For GCC, a char is a signed char.

Parameters

c	Character to be printed

Returns: Reference to OutputStream os; allows operator chaining.

◆ operator<<() [3/14]

OutputStream & OutputStream::operator<< ( const char * string )

Printing a null-terminated string.

Parameters

string String to be printed

Returns: Reference to OutputStream os; allows operator chaining.

◆ operator<<() [4/14]

OutputStream & OutputStream::operator<< ( bool b )

Print a boolean value.

Parameters

b	Boolean to be printed

Returns: Reference to OutputStream os; allows operator chaining.