Learning and cross-platform development (C++)

Question

I am writing a small C++ program for fun and for extending my C++ skill. Since its scope is relatively small, I also planning to try out cross-platform development by making this program support both Windows and Linux.

I reckon my C++ proficiency is sitting somewhere between casual and intermediate level: OO, a bit of templates and design patterns, used STL before and trying to look into it more in details, ... However, while coding this little program, I find that the deeper I dig into C++, the more pain I feel, especially when I come to understanding and dealing with differences between different platform's/vendor's implementation.

The use of cross-platform frameworks like Qt, ACE, Boost seems help to speed up development a lot thus make life easier, but I worry if this will beat my purpose. Can somebody give some advice if there is any "best practice" for doing C++ cross-platform development? Thanks.

Answer 1

Unless you are doing GUI stuff cross platform isn't a big problem.

There are some small issues to do with filesystems ( different / \ separators, allowed characters in filenames etc) but these are at the application level rather than the c++.

Doing major applications gets more complex, you need to handle help, file locations an possibly security and user info in a cross platform way. For simple algorithm type programming there isn't a problem.

Qt is mainly a GUI library, although it has extra cross platform filesystems stuff. STL, Boost, ACE are cross platform but that isn't there main point.

Answer 2

Use them! Seriously. The only reason you may not want to use them is if you plan on working in an environment where they're not available. But, given their cross-platform nature, that's not likely.

You will find that the benefit you get from using them is immense, even if they weren't cross-platform. The "best practice" you speak of is to be able to deliver your "product" as quicly and easily as possible.

I once answered a question from someone who stated he didn't want to use GUI libraries at a level above Xlib. If he'd actually ever used Xlib, he'd know the pain we'd all felt when forced to code at such a low level of abstraction. This makes about as much sense as wanting to code in assembler because C/C++?Python/Perl/everthting-else is simply a higher-level abstarction.

Answer 3

Use gcc. It's available on both Windows and Linux and the libraries and language syntax is identical on both platforms.

For cross platform GUI applications, Qt is a good idea. There is no getting away from having a dependency on a GUI framework if you are trying to achieve platform independence.

Answer 4

Can somebody give some advice if there is any "best practice" for doing C++ cross-platform development?

There are three things:

1. Write your own code so that it's portable

2. Wrap platform-specific APIs behind an abstraction/insulation/utility layer

3. Choose cross-platform libraries

You can choose option #2 and/or #3.

Advantages of #3 over #2 tend to be things like, "It's already written, debugged, and supported"; and the disadvantages are like, "I have to learn it, I might have to pay for it, I can't necessarily support it myself, and it may not do exactly what I want."

Developers will often prefer option #3 instead of #2, especially if it's free open source (which all three of the libraries that you cited are).

Answer 5

i think you can learn a lot from using ACE or equivalent libraries. they will boost your understanding of c++ and design patterns. i think this is the best thing you can do to improve your coding skills.

Answer 6

If your are really interested in making your code as cross-platform as possible, use as many compilers as possible. If you are using Windows and Linux, use VC and gcc, at the minimum. This will ensure that you don't use complier specific features, and that you don't rely on system specific behavior. Use more compilers (Intel, IBM, etc) and OSs (OS X, Solaris) if you have access to them.

Answer 7

this answers are really good and you can make a list for find where is the beginning. but i think you should read some articles about "porting application".not relevant with cross-platform development but this can give you very large perspective about cross platform development. In cross-platform developing, one of more importing thing is memory issues like "endian" (byte order- byte order can show differences for tehnologies or platforms)

Answer 8

You can try using U++ > http://www.ultimatepp.org/index.html

Answer 9

use boost. they take care of cross-platform stuff for you.

boost::filesystem is a great example