Linux平台下的C ++编程

Question

I am a software engineer and i work in VC++, C++ in WIndows OS.

Are there any major differences when it comes to coding in C++ in Linux environment.

Or is it just some adjustments that we have to make when we need to code in C++ in Linux.

Answer 1

It would depend on the types of projects you've worked on and what native windows APIs you made use of. For example if you used the native Windows API for everything, you're going to have a pretty big task ahead of you, it'd be worth making your project(s) work nicely with Wine instead.

In the Linux environment you have the man pages, quite detailed documentation of almost everything :). As mentioned above, look at POSIX, and while I recommend Qt - it provides a LOT of abstractions for things you might want to learn to do the Linux way (eg sockets, filesystem...)

Answer 2

1. Use the POSIX API instead of the Win32 API.
2. Use gtkmm, Qt, or wxWidgets instead of MFC.

Answer 3

Linux programming world is very different from you are familiar with in Windows world. You have to understand it and get used to it. Once you understand you will not want to come back.

1. You have many small/good tools that works with each other rather then all-in-one MSVC solution. For example:

   In Linux you have a compiler as stand-alone tool (Gnu compiler collection), you have build system as stand-alone tool (autotools, CMake). You have GNU Debugger as stand alone tool and you have very good editors as stand alone tool (like hard core vim/emacs).

   There are integrated development environments like Eclipse, Netbeans, KDevelop, Anjuta but still you have to understand how stuff works.

   You should understand that each separate tool is very powerful and integrates with others.

2. OS Level API is designed for simplicity. You'll rarely will find calls like CreateProcessEx with bizzilion parameters rather you have simple fork() + exec() . man is you real friend in all connected to system API and standard C library.

3. GUI - You have two big GUI libraries Qt/GTK. Qt is great C++ library that makes GUI development enjoyable work (unlike MFC). GTK has both C and C++ APIs GTK and GTKmm (no experience with them).

4. i18n/l10n/unicode - this is where Linux programming makes life easier. Almost everything is UTF-8. No wide API crap, no issues with opening Chinese file names with simple fopen or ifstream, no 3rd part library that can't open file with Unicode name. Great built in tools available like gettext, and good translation toolkits like KBabel.

5. Libraries - this is where Linux programming makes you hate Windows. Almost every single free library is already installed or available with simple apt-get or yum install . no debug/release incompatibility crap, no DLL_EXPORT-ing, simple robust, making shared objects is as simple as working with static libraries (and most do not use static libraries at all).

My $0.02

(I'm Linux programmer that have deal a lot with windows development)...

Answer 4

It depends on how many windows-specific things you've been using. The standard part of C++ is the same, but using that will not get you much further than command-line applications.

There's also the whole makefile-instead-of-letting-VS-build-for-you thing. Depending on what tool (or IDE) you decide to use in Linux, that could be a big difference.

Answer 5

I have worked quite a bit on both platforms and like them both, but in general I found most developers to like one and hate the other.

I would describe *nix environment as "geek friendly": many excellent and very flexible tools on your disposal. Some of them introduce hard learning curve, and some are simply broken but still popular for some reason (make) but if you are willing to invest some time in properly learning them, the reward is high. In fact, I use many *nix tools even when working on Windows: vim, grep, perl, etc...

On the other hand, Windows platform offers Win32 API which has way more functionality than POSIX, is very well documented and supported by very good tools. Debuggers on Windows (especially windbg) are generally more powerful that any *nix debugger I have tried, although gdb is generally good enough for most tasks. Deployment of executables is also easier than in Linux world - in fact the only truly reliable way to deploy software on Linux is to ship source code and build it on clients' machines via config/make.

Answer 6

我建议使用像SCons这样的Buildsystem，它在Linux和Win32上运行良好。

Answer 7

Take a look at the source to some open-source project that runs on both Linux and Windows. Typically, over 80% of the code is identical, and the bigger the project the less the system-specific part tends to be. Unfortunately, there can be hard parts (threading, non-blocking network IO, GUI details) in the system-specific code.

Answer 8

There are some major differences that I can think of:

• Tools. Good and bad points. If you are used to Visual Studio, there is nothing quite like that available. Each Linux IDE has some issues. On the other hand, especially debugging tools are very good. But all in all, you are supposed to create your own working environment from what's available.
• API's. Documentation varies wildly. Some components are well documented, but often you end up reading the source code to figure out how something is supposed to work. On the other hand, you have source code so eventually you have all the tools possible to figure out why something doesn't work.
• The Linux programming community is usually very good as long as you remember to behave and you find the right places. SO isn't half bad in some issues, but sometimes you need to find other places.
• Things are not quite as automatic as you might have learned in the Windows world. Yes, some tools allow you to create projects without Makefile knowledge, but really, you should learn how to use them. In Windows it's much more common that you never edit the project files (eg Makefiles) by hand.
• If you want to work in kernel space (drivers etc) C is a better bet than C++ since the kernel is written with that.
• And I agree with people suggesting Qt. Very nice widget set. Beats at least Swing (yes, I know, it's Java) hands down. And Qt Creator isn't half bad.
• Don't underestimate the power of shell scripting! Something very few Windows programmers have figured out, but you can do a hell of a lot with them to help your work.

Answer 9

A typical windows programmer who is used to Visual C++ might find the following aspects of Linux C++ programming novel, or difficult:

1. Linux programming isn't linux programming, it's Unix programming. Unix programming's roots go back a lot further than the MS-DOS roots of Windows, and it shows in a lot of places.

2. Windows programmers tend to think about the environment, they tend to think about the IDE tools (your GUI editor, compiler, debugger) first. Unix programmers tend to be arranged in various tribes, many core Unix (linux) C++ programmers are very comfortable working from the command line without an IDE, and some, I'm sure, use visual-studio style IDEs on Linux, of which there are many.

3. I personally found I had to learn how to read (and maybe write) a makefile, build a bunch of standard Linux/Unix applications from source (and understand how to type my way through steps like 'autoconfiguration' and the various "--command-line-options" one might select there), before I get the feel, and the flavour of the environment.

4. Until you are a seasoned Linux system administrator you might want to stick with the newbie-friendly Linux distributions (like Ubuntu).