Currently I'm coding a python script to compile a C/C++ Linux kernel in the following way:
subprocess.check_call(["make", "-j5"])
subprocess.check_call(["make", "-j5", "modules_install"])
subprocess.check_call(["make", "-j5", "install"])
With these approach the commands are executed in the shell. So I was wondering if there is another way to compile the kernel using python build in libraries?
Ultimately, python isn't a C/C++ compiler, so you need to ship out the compiling to an external program (e.g. gcc). So, there is no way to do this entirely in python.
Note that here python doesn't spawn any shells (although make might). You could try to reproduce what make does entirely in python, (there is a version of make written in python FWIW), but honestly, it's not worth it. You need to spawn subprocesses anyway -- you might as well use the tools which are already in place and "tried and true".
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I have made a small c++ program using glfw, glut and dearImgui on linux machine. As i know, i have written this program so it should build on windows as well.
I would like to send this program to my friend who's running windows and doesn't have a compiler. How is it possible to build a program on a computer without a compiler?
Yes, you can make an installer for your c++ project that should allow your someone on windows to simply install and run it. There are multiple options for doing this but the first way that comes to mind for me is using cmake with cpack, but that would take learning how to use both, which, if you plan on continuing to use c++, is probably worth the effort in the long run.
Short term though, if you want to quickly send your project to your friend in a way he can run it, you can install a cross compiler for windows on your linux machine and just send him a compiled version for windows. Again, there are multiple options but I'm pretty certain MinGW should work for what you need, and be much simpler to learn quickly than cmake with cpack.
For a few years I was writing programs in Visual Studio for Windows and with GCC (Code Blocks) for Linux. Most of my libs compiled seamlessly as they worked both in Windows and Linux. However at the moment I am a bit confused, as I have to create an app using Cygwin. I don't really understand if I am still in UNIX/Linux environment, just running app on Windows by some "emulation", or I am rather on Windows just having access to some Linux/Unix functionality. From what I understood from the FAQ's and documentation it looks like I just should behave like in Linux environment.
All explanations I found in internet usually are very general and don't explain the detailed differences from programmers viewpoint.
Short question: Can I just write programs like I did for Linux without any major changes when using Cygwin?
Maybe.
A lot of code written for Linux will compile in Cygwin with very few problems, which can mainly be fixed by messing with preprocessor definitions.
However, any code written for linux which:
Uses a Linux driver
Directly accesses the kernel
Relies on any code which does either of these two things (and doesn't have a Windows counterpart)
will quite definitely not work, regardless of how much you modify the code.
Much as it tries to, Cygwin cannot fully emulate (yes it is an emulator, of sorts) everything a POSIX system can normally do. Cygwin is not windows, just a conversion layer from its own machine language.
For more information, read cygwin's wikia
Can I just write programs like I did for Linux without any major
changes when using Cygwin?
The platforms are not identical, so you can not realistically expect to write the program in Linux, and then POOF expect it to build and work under Cygwin. But if you don't use things not available under Windows, then you won't need major changes. And you can write non-trivial programs, which will build and work on both, perhaps needing a few #ifdefs in places.
From your question I take it you want to work on Linux, but write programs for running under Cygwin. In that case you must also build and test it in the Cygwin environment all the time, so:
Use version control, commit often. I recommend a DVCS like git or mercurial which have separate commit and push, it will allow you to do commits more freely.
Whenever you commit/push, do checkout/pull and build on the Cygwin host. You can do this manually or automatically (by simple custom script polling the version control, or by Jenkins or something).
When ever your code stops building or working under Cygwin, fix it before continuing with new code.
If Cygwin is not absolute requirement, then I would look into using Qt SDK. It can be used for non-Qt projects too, the MinGW toolchain on Windows is very similar to gcc on Linux. And if you're willing to use Qt, then it has all sorts of platform-independent features for things you might want to do, such as discover locations of standard directories for saving files, use threads, print things, have GUI...
is there any Binary Decision diagram (BDD) is available in windows.i tried to run cudd in vc++6.0..which is mention link
http://web.cecs.pdx.edu/~alanmi/research/soft/softPorts.htm
but it isn't working properly.i get compiler error while running a sample code
I compiled CUDD for Windows, but using MinGW not a Microsoft environment. My goal was that compiler since I use Dev-C as IDE.
I did a first try using Cygwin, but with no luck. The second try was with MSYS, an environment to run unix commands that come with MinGW for Windows. Note that CUDD uses a couple of POSIX libraries (such as ). Luckily they are used only in two secondary functions: CPU stats and a kind of fork that I didn't fully understood. Since I didn't need those, I simply commented the portion of code (in util/cpu_stats.c).
Then you only need to write a Makefile for MinGW in order to link the library!
If you need it, I can send to you the library already compiled.
I'm a whiz with Visual C++, but Linux development is new to me. In Visual Studio, it's easy to trace into any code implemented by the C run time libraries. I just need to make sure the sources are installed and I can step right into any function I'd like -- malloc(), cout::operator<<(), whatever.
I'm trying to develop using Eclipse's C++ package. How can I step into C run time routines there? Since Linux is open-source, how do I step into operating system routines? Seems like it should e possible -- am I missing debug information, source code, or both? Something in my configuration?
I'm using Ubuntu 12.10 at the moment. I'm using g++. I believe I'm using the Eclipse build system as I never imported a makefile project; I just started with a simple "Hello World" project from the C++ project wizard in Eclipse.
After hacking at this a bit:
I've installed the libstdc++6-4.2-dbg package thinking it would be debug symbols for the libstdc library:
sudo apt-get install libstdc++6-4.2-dbg
I've also installed dpkg-dev, since the next step said I needed it:
sudo apt-get install dpkg-dev
I tried installing libc6 sources into a directory under my home:
apt-get source libc6
At this point, trying to step into printf() tells me that printf.c is missing. I can't step into malloc or strlen, which suggests that I don't understand how the C runtime libraries are factored in Linux. How are libc, glib, and libstdc++ different? Which packages do I need?
If I ask Eclipse to open the printf.c file I do have (at ~/eglibc-2.15/stdio-common/printf.c), it doesn't open the file (doesn't adjust the debugging window to show the source) and repaints the window that shows the error message about not being able to find the file. (Can't find a source file at "printf.c" Locate the file or edit the source lookup path to include its location.)
Whilst, as a Kernel developer on Linux, I do agree that using the individual tools separately will be a good thing to learn, and as such Basile's answer is usefuel.
However, the stepping into C runtime libraries should be equally possible with Eclipse. But just because the OS is open source doesn't mean that it supports you clambering around inside it willy nilly - in fact, you CAN NOT step into the OS itself from user-mode code. You nee KGDB (google it), and you definitely need a second computer to attach to the one being debugged, because when you step into the kernel, you will essentially lock up the machine, at the very least in the context you are stepping, but most likely also prevent other work from being done until you get back out from the kernel, so for example, if you step into open(), at some point the entire filesystem may well stop working altogether until you are back out of whatever lock you are holding. This wll certainly upset some software. Note that this is just an example of how things may work unexpectedly when debugging the kernel, not strictly "I've done this and it happened" - I have debugged kernels with debuggers several times, and you do have to be careful with what you do, and you certainly can not run the debugger on the same machine, as the machine STOPS when you are debugging.
Going back to the usermode, which you CAN debug via Eclipse, essentially all you need to do is install the source code for the runtime library you are interested in, and go... Same principle as on Windows with visual studio - except that nearly all software you ever run on a Linux system is available as source code. You may need to recompile some libraries with debugging symbols, and just like in Windows, you need to make sure the debugger knows how to find the source code. Everything else should be handled by the debugger in Eclipse. I spent about three years using Eclipse for both local and remote debugging, and in general, it works. There are quirks in places, but that's the case with almost any debugger.
Good luck.
First, you don't need Eclipse to develop software on Linux. You should better learn to do that with independent tools (command line) like emacs or gedit (as editor), git (version control), make (builder) which runs the gcc or g++ compiler (both gcc & g++ are part of GCC, the Gnu Compiler Collection).
really, you'll learn a lot more by not depending upon Eclipse; it may just hide you the real commands which are doing the job, and you should understand what they really are.
You want to pass the -g -Wall options to GCC. The -g option asks for debug information, and the -Wall options asks for almost all warnings. Improve your code till no warnings are given.
And the operating system is providing syscalls (which are operations provided by the kernel to applications; from the application's point of view, a syscall is atomic so you cannot step into it; however strace may show you all the syscalls done by some execution). If you wanted to step by step inside system libraries like libc you need the debugging variant of it (e.g. some libc6-dbg package). But there is usually no need to dive inside system libraries.
See http://advancedlinuxprogramming.com/
Then, you will use gdb to debug the binary program.
So, step by step instructions inside a terminal:
edit your source files with emacs or gedit
learn how to use GCC: for a single source C++ program compile it with g++ -Wall -g source.cc -o progbin and type ./progbin in your terminal to run it. Only when the program is debugged and satisfactory would you compile it with optimizations (by giving the -O or -O2 flag to gcc or g++)
Use gdb to debug a program (compiled with -g).
for a multi-file C++ program, consider learning how to use make
use a version control system like git
For beginners, I suggest to avoid Eclipse, because it just hides to you what is really happening underneath (Eclipse is simply running other tools like the above commands)
Software development under Linux requires a different mindset than under Windows: you really are using your own loose combination of independent tools, so better to learn a bit each of them.
NB. to step inside "system" functions like malloc (which is above syscalls like mmap) you need the debug variant of the libc package with aptitude install libc6-dbg, and you need to set LD_LIBRARY_PATH to /usr/lib/debug etc...
I haven't done much coding in C++, but I? noticed that I have to run these build scripts for everything. HOw do people do these on windows machines? I am thinking about running a virtual machine anyway, so I don't have to fill my machine with python and other such installations.
How does everyone else on windows do it?
There's always cygwin if you want to run the standard UNIX type tools, such as make, etc.
MinGw comes with a gcc-compatible Compiler and Make System. So if you want to use makefiles, this is a possible way. If you need an IDE, Eclipse CDT might be for you.
However, I prefer Visual Studio, mainly for personal reasons (experience gathered over years) and debugging seemed to work somewhat better.
You might also want to look at CMake for a platform independet build tool.
AFAIK you can simply get the python executable and put them somewhere where the scripts can access them, inside your project code. That way you don't have to install it in the system and you don't have to use a virtual machine either.