Cplusplus - Revision history

Graggle at 11:10, 20 April 2026

2026-04-20T11:10:02Z

← Older revision		Revision as of 11:10, 20 April 2026
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	I'll get around to this someday. I'm still learning too you know!		I'll get around to this someday. I'm still learning too you know!

	[[Category:~~Helpdesk~~]]		[[Category:Archive]]

Coconut: opcode only specifies an instruction. Machine code (of which assembly language is a human-readable representation) is accurate.

2008-10-22T23:13:24Z

opcode only specifies an instruction. Machine code (of which assembly language is a human-readable representation) is accurate.

← Older revision		Revision as of 23:13, 22 October 2008
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	The page [[Programming On Redbrick]] explains how to compile programs written in C++. Here we will go into more depth as to how the compiler g++ works.		The page [[Programming On Redbrick]] explains how to compile programs written in C++. Here we will go into more depth as to how the compiler g++ works.

	A compiler works by translating your programming language (in this case, C++) into ~~opcode~~, which is the basic language that a processor understands. While C++ is a universal language (source code written on one architecture will generally work on another unless special libraries are used), programs must be recompiled if they are to be used on different architectures - for example, if you are compiling on murphy, which uses the UltraSPARC architecture, you will have to recompile your program if you wish to use it on carbon or deathray, which use the Intel x86 architecture, because UltraSPARC and x86 assembly languages are completely different.		A compiler works by translating your programming language (in this case, C++) into machine code, which is the basic language that a processor understands. While C++ is a universal language (source code written on one architecture will generally work on another unless special libraries are used), programs must be recompiled if they are to be used on different architectures - for example, if you are compiling on murphy, which uses the UltraSPARC architecture, you will have to recompile your program if you wish to use it on carbon or deathray, which use the Intel x86 architecture, because UltraSPARC and x86 assembly languages are completely different.

	g++ is the free, open-source C++ compiler which is included with many distributions of Linux as part of the gcc package, the latter of which is a C compiler. Other popular C++ compilers include Borland C++ and Microsoft Visual C++, however these are proprietary. gcc (and g++) is the most widely ported and universally available compiler in the world.		g++ is the free, open-source C++ compiler which is included with many distributions of Linux as part of the gcc package, the latter of which is a C compiler. Other popular C++ compilers include Borland C++ and Microsoft Visual C++, however these are proprietary. gcc (and g++) is the most widely ported and universally available compiler in the world.

Gavin: remove some of the crap

2008-03-06T16:27:49Z

remove some of the crap

← Older revision		Revision as of 16:27, 6 March 2008
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	'''Under construction~~, LOL~~.'''		'''Under construction.'''

	''If you have any problems with this tutorial or want to give feedback, ask questions or get additional help, please e-mail coconut<at>redbrick<dot>dcu<dot>ie or, for general [[Helpdesk]] queries, helpdesk<at>redbrick<dot>dcu<dot>ie~~. Go go Power Rangers..~~.''		''If you have any problems with this tutorial or want to give feedback, ask questions or get additional help, please e-mail coconut<at>redbrick<dot>dcu<dot>ie or, for general [[Helpdesk]] queries, helpdesk<at>redbrick<dot>dcu<dot>ie. ''

	'''C++''' is an object-oriented programming language, developed as a superset of the language [[C]], which means that the language is essentially C with more features, hence the name. However, it has since evolved into a separate language and ~~compatiblity~~ with C is no longer guaranteed.		'''C++''' is an object-oriented programming language, developed as a superset of the language [[C]], which means that the language is essentially C with more features, hence the name. However, it has since evolved into a separate language and compatibility with C is no longer guaranteed.

	It is a very popular all-purpose language which is commonly utilised for game programming, and in many respects is quite similar to [[Java]], another object-oriented language.		It is a very popular all-purpose language which is commonly utilised for game programming, and in many respects is quite similar to [[Java]], another object-oriented language.
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	The page [[Programming On Redbrick]] explains how to compile programs written in C++. Here we will go into more depth as to how the compiler g++ works.		The page [[Programming On Redbrick]] explains how to compile programs written in C++. Here we will go into more depth as to how the compiler g++ works.

	A compiler works by translating your programming language (in this case, C++) into ~~assembly language~~, which is the basic language that a processor understands. While C++ is a universal language (source code written on one architecture will generally work on another unless special libraries are used), programs must be recompiled if they are to be used on different architectures - for example, if you are compiling on murphy, which uses the UltraSPARC architecture, you will have to recompile your program if you wish to use it on carbon or deathray, which use the Intel x86 architecture, because UltraSPARC and x86 assembly languages are completely different.		A compiler works by translating your programming language (in this case, C++) into opcode, which is the basic language that a processor understands. While C++ is a universal language (source code written on one architecture will generally work on another unless special libraries are used), programs must be recompiled if they are to be used on different architectures - for example, if you are compiling on murphy, which uses the UltraSPARC architecture, you will have to recompile your program if you wish to use it on carbon or deathray, which use the Intel x86 architecture, because UltraSPARC and x86 assembly languages are completely different.

	g++ is the free, open-source C++ compiler which is included with many distributions of Linux as part of the gcc package, the latter of which is a C compiler. Other popular C++ compilers include Borland C++ and Microsoft Visual C++, however these are proprietary. gcc (and g++) is the most widely ported and universally available compiler in the world.		g++ is the free, open-source C++ compiler which is included with many distributions of Linux as part of the gcc package, the latter of which is a C compiler. Other popular C++ compilers include Borland C++ and Microsoft Visual C++, however these are proprietary. gcc (and g++) is the most widely ported and universally available compiler in the world.
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	mkdir C++		mkdir C++

	This will create a directory called "C++" in your home directory. ~~Open up~~ this directory by typing		This will create a directory called "C++" in your home directory. Enter this directory by typing

	cd C++		cd C++

	Now you're ready to create your first C++ program. For this tutorial, we are going to use the [[nano]] editor~~, as it is simpler than the alternative, vim~~. Make a new C++ source file, that we will call "first", with		Now you're ready to create your first C++ program. For this tutorial, we are going to use the [[nano]] editor. Make a new C++ source file, that we will call "first", with

	nano first.cpp		nano first.cpp

Coconut at 16:12, 6 March 2008

2008-03-06T16:12:22Z

← Older revision		Revision as of 16:12, 6 March 2008
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	a and b are passed as ''parameters'' to the add function - they are then immediately added together and the answer is returned. Experiment with this code to do different things.		a and b are passed as ''parameters'' to the add function - they are then immediately added together and the answer is returned. Experiment with this code to do different things.

	===More advanced C++===		==More advanced C++==

	I'll get around to this someday. I'm still learning too you know!		I'll get around to this someday. I'm still learning too you know!

	[[Category:Helpdesk]]		[[Category:Helpdesk]]

Coconut at 16:12, 6 March 2008

2008-03-06T16:12:06Z

← Older revision		Revision as of 16:12, 6 March 2008
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	==g++==		==g++==

	The page [[Programming On Redbrick]] explains how to compile programs written in C++. Here we will go into more depth as to how the compiler g++ works.		The page [[Programming On Redbrick]] explains how to compile programs written in C++. Here we will go into more depth as to how the compiler g++ works.

	A compiler works by translating your programming language (in this case, C++) into assembly language, which is the basic language that a processor understands. While C++ is a universal language (source code written on one architecture will generally work on another unless special libraries are used), programs must be recompiled if they are to be used on different architectures - for example, if you are compiling on murphy, which uses the UltraSPARC architecture, you will have to recompile your program if you wish to use it on carbon or deathray, which use the Intel x86 architecture, because UltraSPARC and x86 assembly languages are completely different.		A compiler works by translating your programming language (in this case, C++) into assembly language, which is the basic language that a processor understands. While C++ is a universal language (source code written on one architecture will generally work on another unless special libraries are used), programs must be recompiled if they are to be used on different architectures - for example, if you are compiling on murphy, which uses the UltraSPARC architecture, you will have to recompile your program if you wish to use it on carbon or deathray, which use the Intel x86 architecture, because UltraSPARC and x86 assembly languages are completely different.
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	a and b are passed as ''parameters'' to the add function - they are then immediately added together and the answer is returned. Experiment with this code to do different things.		a and b are passed as ''parameters'' to the add function - they are then immediately added together and the answer is returned. Experiment with this code to do different things.

			===More advanced C++===

			I'll get around to this someday. I'm still learning too you know!

	[[Category:Helpdesk]]		[[Category:Helpdesk]]

Coconut: /* Executing system commands in C++ */

2008-03-06T16:03:42Z

Executing system commands in C++

← Older revision		Revision as of 16:03, 6 March 2008
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	...like so!		...like so!

			However, it is recommended that you '''not''' use system commands in your code for something as trivial as clearing the screen. It's a resource hog and leaves a gaping security hole in your C++ program. There is a better way to do this in C++, however it requires advanced knowledge of the language and is available below under ''Advanced''.

	==Functions: The Basics==		==Functions: The Basics==

Coconut at 11:36, 26 February 2008

2008-02-26T11:36:02Z

← Older revision		Revision as of 11:36, 26 February 2008
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	...like so!		...like so!

			==Functions: The Basics==

			It's now time to move on to '''functions'''. A function is basically the same thing as a method in Java: it is a sequence of commands which can be called upon at any time, passed parameters and set to return a value.

			main() is a function - the default function for a C++ program. But what if you have some code that you don't want to put into main? Use another function.

			Let's say we want to add two numbers together and print out the result. The code could look something like this:

			#include <iostream>

			using namespace std;

			int add(int a, int b)
			{
			return a + b;
			}

			int main()
			{
			int a = 2;
			int b = 5;

			cout << add(a,b) << endl;

			return(0);
			}

			This program adds 2 and 5 together to get 7, and displays this answer on-screen.

			a and b are passed as ''parameters'' to the add function - they are then immediately added together and the answer is returned. Experiment with this code to do different things.

	[[Category:Helpdesk]]		[[Category:Helpdesk]]

Coconut at 09:12, 13 January 2008

2008-01-13T09:12:10Z

← Older revision		Revision as of 09:12, 13 January 2008
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	For example, if you want the loop to end early when a certain condition is met, just use an if statement inside the loop and have the loop break if this condition is met.		For example, if you want the loop to end early when a certain condition is met, just use an if statement inside the loop and have the loop break if this condition is met.

			==Executing system commands in C++==

			It is possible to execute system commands from within your C++ program. If your program is command-line only, you can execute simple commands such as those to clear the screen, etc.

			If you're using Linux, the code is

			system("clear");

			You can also do this if you're running Windows (although why would you want to?) The DOS clear command is "cls"

			system("cls");

			...like so!

	[[Category:Helpdesk]]		[[Category:Helpdesk]]

Coconut at 19:04, 14 December 2007

2007-12-14T19:04:44Z

← Older revision		Revision as of 19:04, 14 December 2007
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	''If you have any problems with this tutorial or want to give feedback, ask questions or get additional help, please e-mail coconut<at>redbrick<dot>dcu<dot>ie or, for general [[Helpdesk]] queries, helpdesk<at>redbrick<dot>dcu<dot>ie. Go go Power Rangers...''		''If you have any problems with this tutorial or want to give feedback, ask questions or get additional help, please e-mail coconut<at>redbrick<dot>dcu<dot>ie or, for general [[Helpdesk]] queries, helpdesk<at>redbrick<dot>dcu<dot>ie. Go go Power Rangers...''

	'''C++''' is an object-oriented programming language, developed as a superset of the language C, which means that the language is essentially C with more features, hence the name. However, it has since evolved into a separate language and compatiblity with C is no longer guaranteed.		'''C++''' is an object-oriented programming language, developed as a superset of the language [[C]], which means that the language is essentially C with more features, hence the name. However, it has since evolved into a separate language and compatiblity with C is no longer guaranteed.

	It is a very popular all-purpose language which is commonly utilised for game programming, and in many respects is quite similar to [[Java]], another object-oriented language.		It is a very popular all-purpose language which is commonly utilised for game programming, and in many respects is quite similar to [[Java]], another object-oriented language.

Coconut at 19:04, 14 December 2007

2007-12-14T19:04:29Z

← Older revision		Revision as of 19:04, 14 December 2007
Line 2:		Line 2:

	''If you have any problems with this tutorial or want to give feedback, ask questions or get additional help, please e-mail coconut<at>redbrick<dot>dcu<dot>ie or, for general [[Helpdesk]] queries, helpdesk<at>redbrick<dot>dcu<dot>ie. Go go Power Rangers...''		''If you have any problems with this tutorial or want to give feedback, ask questions or get additional help, please e-mail coconut<at>redbrick<dot>dcu<dot>ie or, for general [[Helpdesk]] queries, helpdesk<at>redbrick<dot>dcu<dot>ie. Go go Power Rangers...''


	'''C++''' is an object-oriented programming language, developed as a superset of the language C, which means that the language is essentially C with more features, hence the name. However, it has since evolved into a separate language and compatiblity with C is no longer guaranteed.		'''C++''' is an object-oriented programming language, developed as a superset of the language C, which means that the language is essentially C with more features, hence the name. However, it has since evolved into a separate language and compatiblity with C is no longer guaranteed.