What are the most F.A.Q. on this forum?

[twicker]

Which would you say are the most frequently asked questions here?
The FAQ article (information section) badly needs a rewrite, and the forum's input can be really valuable for that.

[Duoas]

This is a very good question.

Introduction to C++
What is C++?
Is C++ a proprietary language? Do I need to pay to use it?
What are the C++ Language Standards?
How do I know if my compiler supports a Standard?

Do I need to learn C or another language first?
How can I best learn C++?
What do I need to get started?

What is OOP (Object Oriented Programming)?
What are templates and "generic programming"?
How do I make windowed (GUI) programs?
What is Visual C++? What does "visual programming" mean?

Arrays, Strings, Sequences, etc strings
008-0 - Split a string?
008-1 - Parse CSV data?
008-3 - Parse XML data?
078 - - C-strings and pointers?
008-2 - strtok()!
017-0 - toupper() or tolower() a string?
017-1 - Compare strings without case-sensitivity?
055 - - trim() a string?
048 - - Use strings in a switch statement?
081 - - Linked lists (basics, singly, doubly)
082 - - Print an array/vector/list/etc

arrays
044-0 - sizeof() doesn't work on arrays!
044-0 - Determine the dimension(s) of my array?
044-1 - Pass my (N-dimensional) array to a function?
044-2 - Pass any (N-dimensional) array to a single function?

sequencing
060-0 - Sort stuff?
060-1 - Sort stuff myself?
074 - - Reverse a string/array/etc?

Beginners / Homework
020 - - Palindromes
022 - - Is there a NULL for int, float, etc?
023 - - Pointers vs. References
028 - - Headers and Source Files (.h and .cpp files)
031 - * Why is my program skipping input? <i>this will also include some beginner stuff in addition to the link to the I/O section</i>
035-0 - Convert a number to/from a char?
035-1 - Convert numbers to/from a string?
041-0 * Overloading the Assignment Operator
041-1 * Overloading Comparison Operators (< == <= > >= !=)
041-2 * Overloading << (the Stream Insertion Operator)
041-3 * Overloading >> (the Stream Extraction Operator)
042 - * Return more than one thing from a function?
043 - * Read a specific line from a file?
044-0 * sizeof() doesn't work on arrays!
044-1 * Determine the dimension(s) of my array?
044-2 * Pass my (N-dimensional) array to a function?
044-3 * Pass any (N-dimensional) array to a single function?
045 - * Random numbers?
047-0 - Star Pyramid
047-1 - Center text on the screen?
047-2 - Positioning text / stars / menus / etc?
055 - * trim() a string?
065-0 - Caesar ciphers?
065-1 - XOR ciphers?
065-2 - Encrypt and decrypt stuff?
071 - * i = ++i + i++; <i>not sure where to put this one</i>
072 - * operator precedence issues
079 - - Why doesn't 2^3 equal 8?
073 - * What C++ books should I buy?
074 - * Reverse a string/array/etc?
077 - - Recursion
083 - * logic problems (why does "if (x = 7 || 8)" always evaluate true?)

Compiling and Linking
053 - - troubles with verbose template errors
056 - - issues with linking (static and dynamic)
062 - - (error messages due to) outdated compilers
063 - - compiling
066 - * what the heck are calling conventions and why do I need them?
069 - - using make

Dealing with Numbers
004 - * how do I read/validate a <number> (making sure it is a <number>, and nothing else)
035 - - how do I convert numbers to chars or strings, or vice-versa
038 - - anything about special numbers: +INF/-INF, NAN, MAX_INT, etc.
045 - - confusion over random numbers (specifically, how to properly use [code]srand[/b]() and rand() )
054 - - how do I "type" a user input (as an integer, a float, etc)
057 - - issues with rounding
064 - - issues with floats (see also #38)
076 - - how do I convert between radices/how do I do base conversion (dec to hex, etc)?

Functions, Arguments, Return Values
019 - - confusion over void
042 - - how do I return multiple values from a function
050 - - problems with va_args, etc
066 - * what the heck are calling conventions and why do I need them?
078 - - anything about return values
080 - - default arguments in C99

Images, Graphics and GUIs
002 - - how do I read/write <image file format>
012 - - anything about <graphics.h> / WinBGIm
024 - - how do I get a screenshot / the pixel color under the mouse / etc. (for stuff outside my app)
051 - - how do I create a GUI (application)

Input and Output
004 - * how do I read/validate a <number> (making sure it is a <number>, and nothing else)
018 - * how do I make my application use multiple languages
030 - - how do I know if the standard streams are redirected to/from file(s)
031 - - my program skips user input (because OP is mixing >> and getline()); cin >> string doesn't work with spaces; etc.
032 - - how do I read/write binary data
033 - - how do I serialize my class (this is almost never asked correctly, as the OP does not know the word "serialization")
034 - - confusion over EOF issues (such as looping on EOF, or trying to read EOF, etc)
039 - - how do I make w[cout|cin|string|stream|etc] work? (it won't, at least without some serious locale hacking - better to use a library)
040 - * how do I download files from the internet (programmatically, of course)
043 - - how do I read a specific line/datum from a file (usually a text file)
054 - - how do I "type" a user input (as an integer, a float, etc)
070 - - structure packing and dealing with binary data (see also #32)
075 - - how do I open a file/using a user-input string?

Language and Style
003 - - how do I repeat main()
007 - - anything about goto
015 - - what indent style do you use
016 - - anything about Hungarian Notation
037 - - what IDE do you use
041 - - anything about overloading operators, particularly: assignment, comparision, and stream insertion/extraction
052 - - troubles with templates
061 - - void main() vs int main() (see also #3 and #19)
067 - - entry points (see also #63)
071 - * issues with the increment & decrement operators and sequence points
072 - - operator precedence issues (see also #71)
073 - - what C++ book should I get?
083 - - logic problems (why does "if (x = 7 || 8)" always evaluate true?)

Parent / Child / Processes
005 - - how do I write a virus/keylogger/other script-kiddie nonsense
010 - - how do I execute another program (safely)
011 - - how do I manipulate another application (i.e. control it in some way)
029 - - how do I include external data (such as images) in my executable
049 - - problems with fork(), etc

Working with the Console
001 - - how do I PAUSE (and variations, like how do I keep my console window open)
006 - - how do I clear the screen
009 - - how do I change the color of my text
013 - - how do I check if/wait until a key is pressed and/or read a single key without stopping the program
014 - - how do I delay (sleep)
046 - - how do I set/get the cursor position on the console

Miscellaneous
018 - * how do I make my application use multiple languages
021 - - how do I play a sound; in the background; loop; stop it; etc.
025 - - how do I write an OS
026 - - how do I write the next big MMORPG (or any game at all)
027 - - anything about compression
036 - - how do I read a password; other stuff with passwords
040 - - how do I download files from the internet (programmatically, of course)
048 - - how do I switch on strings
053 - * troubles with verbose template error messages
065 - * how do I write encryption algorithms (everything from Caesar ciphers to the next AES) [advanced]
068 - - CLI/MFC/etc issues

Not yet organized
058 - - how do I handle command-line arguments
059 - - any of the above in Linux or cross-platform

[edit] Added numbers to suggestions for reference

[edit2]
I have begun to organize the items into sections.

Some of the items will be listed more than once, sometimes in multiple sections. Whenever this happens, there is an asterisk (*) next to the name of the referring item. (The original has a dash.)

Also, I think the Arrays, Strings, Sequences, etc. section needs some stuff about iterators, linked lists, etc.

Newly added items in bold.

[Albatross]

I think that out of those, the question we get the most of is how to make a game. It's usually asked by people first starting C++, and I usually tell them that they'll have to have years of experience in C++ before they'll be have the skills necessary to create a good (3D) game. 2D games somehow require a lot less skill, IMO. :)

-Albatross

[ResidentBiscuit]

-How to sort this array? (Or any other sequential container)
-Oh and what sort should be used?
-How do I Google?
... Ok that one was a joke but I think a lot of these questions could be translated to that
-Anything with overloading
-Why not void main()?
-Why this random obscure error? Oh yea I'm using bloodshed dev C++
-Anything about the process of linking and compiling
-How do I get past programming console apps?
-Writing my own encryption algorithm...
-How come my floats never turn out right after 1000 calculations?

Thats about all I can think of. Duoas up there took all the good ones :(

[Computergeek01]

I haven't looked at the FAQ in a while so I applogies for any duplicates, I'll look after posting this then come back and edit it.

- What is a Calling Convention and why is it required before using certain functions\features of an API or library.

- This one is not easy to do as an FAQ bullet but I think expalining what Main() or any other entry point like WinMain(...) and DLL_Main() is and what is expected of them from the compiler and the OS would save newer programmers some confusion. This one might be too platform dependent but I thought I would throw it out there.

- In the Windows Forum I see a lot of confusion between C\C++ and C++\CLI, mostley about where one begins and the other ends. Maybe an entry explaining what the difference between C++ and C++\CLI are would be helpful.

- An entry quickley explaining that Interprocess Communication and Remote Procedure Calls are API as well as platform specific in nature could help some users know where to look next.

- A Dictionary of common but C\C++ and programming specific terms would be nice, that would even help me some of the time.

- What is a Race Condition and how to avoid them through appropriate planning and design.

EDIT More questions I see a lot:

- How do I pass my array\stl container to a function?

- What is the difference between a Compiler and an IDE?

[Luc Lieber]

Might be out of the scope of the FAQ, but a lot of people are having difficulty understanding how linking works when trying out a new library. I think that the fault falls on poor documentation on the library maintainers' end, but nevertheless someone needs to explain what the errors mean. It's an offsetting feeling when you follow a tutorial step-by-step, just to find out it's broken with the new library version that's been released. Having a working knowledge of how linking works would help alleviate some of the "Undefined Reference Syndrome" cases going around.

* Also, how to make my program wait for X time units



-- Infrequently Asked Questions --

* Also, what's the difference between runtime libraries again? MT, MTD, MD, MDD?

* Also, what is make, and how can I build projects that use it on Windows?

[Null]

- what are differences between 32 bit and 64 bit applications?
- something about structure packing
- what's the difference between ++i and i++ ?

[Moschops]

Why do I need pointers?

Having a working knowledge of how linking works would help alleviate some of the "Undefined Reference Syndrome" cases going around.

Alleviate that and so much more. It's why I recommend not using an IDE for at least the first fortnight. This view is not popular :(

[Duoas]

Should we number our suggestions so we can vote on the best candidates?

[L B]

There should definitely be a section on how to understand preprocessor, compiler, and linker errors.

[hamsterman]

- why 1/2=0 and how to solve it. Maybe that is the same as Duoas's 57th though..
- confusion about pointers and arrays (including T (*)[N] and multidimensional arrays)

My favourites so far are Duoas's 4, 8, 35 and 28 as I find myself spending a lot of time on them. Luckily there is http://cplusplus.com/articles/S3wTURfi/ (this one, I think, is a bit lacking) , http://cplusplus.com/articles/D9j2Nwbp/ and http://cplusplus.com/articles/Gw6AC542/ . I don't think I've seen anything about 8 though.

Which brings up a point. Some of the topics that need to be covered already have articles about them. Maybe it would be a good idea to add links to them in the FAQ.

[CodeMonkey]

twicker wrote:

The FAQ article (information section) badly needs a rewrite

Is it worth thinking in terms of two FAQs? One focused on the sort of questions asked by someone deciding weather or not they want to learn C++, The sort of how long will it take? Should I learn C first? etc.

Then have another possibly pinned at the top of the forums with the sort of How to do X Y Z type questions. The second one can be built mainly of links to articles that are relevant to the question.



General questions about C++.
What is the best book to learning C++?
How long does it take to learn C++?
Do I need to learn C before C++?
It C++ a good choice as a first language?
Does C++ have a future?
Will you help me with my homework?
Can I use C++ for…?

[moorecm]

How can I make a triangle/pyramid of asterisks (and a few other variations)?

*
**
***
****
*****

[sloppy9]

+1 hamsterman, those are definitely the most common problems I see.

_{Beginner: How do I use something?
Member: *links to the something reference*
Beginner: I didn't know this site had a reference, thanks!
Member: You're welcome!
Beginner: Could I see an example??
Member: *banging head on desk*}

[L B]

Don't all the references have examples??

[Cubbi]

In the two months I've been on this forum so far, I've seen at least four order-of-evaluation questions (what is the result of n = n++; or n = ++n + n++; or cout << n << n++;)

[Grey Wolf]

That looks like a lot of work, where do we get started? :0)

[Duoas]

I think that the FAQ, if it is to be comprehensive, needs to be subdivided into logical sections, which should help the user narrow down his problem to the appropriate FAQ.

I don't know yet how much work twicker wants to put into this... but we really should try to organize somewhat here before moving too much forward; the kind of work twicker will need to put into this will depend on its organizational needs.

@ResidentBiscuit
- overloading --> #41
- get past console apps --> #51 (but good phrasing, perhaps we should have it link to the same subject matter?)
- writing one's own encryption algorithm might be a little too much for a FAQ, other than to say, "good luck" and "here are a few links to get you started".

@Computergeek01
- CLI (etc) is not C++, so I'm not sure that the forum FAQ really needs address it (IMHO). Perhaps we could make a FAQ entry to explain that there are additional libraries that are designed around C and C++ and tightly integrated into IDEs, like CLI and MFC and the like...
- IPC, RPC, and other platform-specific stuff seems me to better belong in an Article
- Race Conditions likewise need an Article, since I don't think that anyone who doesn't understand why the program is misbehaving will be able to glean if from a list of FAQs...
- array/container arguments --> #44
- Compiler vs IDE --> #63

@Luc Lieber
- wait N units of time --> #14
- runtime libraries and linking issues --> #56

@Null
- Can you explain what you mean by "issues with 32 and 64 bit applications"? Is this Article material or compiling/linking issues?

@Moschops
- Is "why do I need pointers" part of #23 or a separate issue?
(Come to think about it, the tutorial is pretty good on presenting pointers and references, IIRC. Exactly what pointers issues do people have? [I typically ignore posts about them].)

@L B
- see #56

@hamsterman
- 1/2=0 is not the same as #57, but it is of the same category.
- What do you dislike about Zaita's article? (I'm not picking a fight here, just wondering.)
I agree with the FAQ with links to Articles idea.

@moorecm
- Part of the purpose of those homeworks is to think about how to work with loops. I think it is a real disservice to give people answers on that.
However, I do think it is a good idea to have something about working with spacing. (I've been thinking about an Article addressing it for a while. Alas for time.)

@Grey Wolf
Yaaay! Glad to see you back!

:O)

[Computergeek01]

@ Duoas:
- CLI: We all agree that C is not C++ either but we still get\answer questions about it. I actually broke down and started learning this for a bit and trust me, you won't see a difference without at least a few years experiance in both. After taking a compiled executable apart I got the impression that it's really C++ with training wheels. I think that pointing out some of the differences like you said would be a great thing to post on a new FAQ.

- IPC\RPC: That is a very good point, I think I'll try my hand at that.

@ Everyone: Regarding pointers, we can beat this dead horse until the end of time. The truth is that it just "clicks" for people. The idea is a little abstract but the tutorial here is a great resource (it's what taught me how to use them). Besides can you even cover pointers in a bulleted format like an FAQ?

[moorecm]

Duoas wrote:

@moorecm
- Part of the purpose of those homeworks is to think about how to work with loops. I think it is a real disservice to give people answers on that.
However, I do think it is a good idea to have something about working with spacing. (I've been thinking about an Article addressing it for a while. Alas for time.)

Homework problems are a significant amount of traffic here. They should perhaps be grouped in their own section somewhere.