I'm planning to install PyPy on my system. I already have CPython implementation existing on my system. Will installing PyPy affect this existing system implementation in any way ?
In nutshell, I want to know if PyPy and CPython an co-exist on any OS without any issues ? I'm attempting this on Mac OS X 10.6
They can physically co-exist without any issue.
I am writing this in a system which has both Python 2.7.3, Pypy 1.9 and Python 3.2.3 installed.
Apart from that, Alex Martelli (who is an expert pythonista) in his book Python in a Nutshell, seems to concur. To quote him:
"Download and install all of them. They are free and coexist without
issues."
With them he refers to CPython, IronPython and Jython, but the same can apply to Pypy.
Also, you should not take my word for it. Download and install it and try it. Naturally, you won't have any issues.
Related
I'm currently working on an application that I would like to publish to many distributions. So far, I've done all my testing on one distribution at a time (compile and run on the same distro). But when I take the outputted AppImage from compilation on my main computer (Arch Linux), and try to run it in a vm (Ubuntu 20.04), it gives me the error below:
gabriel#gabriel-VirtualBox:~/Downloads$ ./Neptune.Installer-x86_64.AppImage ./Neptune.Installer-x86_64.AppImage: /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.34' not found (required by ./Neptune.Installer-x86_64.AppImage)
What possible solutions are there to this? I've considered statically linking the library, but I'm unsure if that might cause licensing issues, as my program is not open source. Apart from that, I might consider simply compiling my program on a very old distribution such as Ubuntu 12 or something, but I won't know how well that carries over to other distros (for example, will my program still work on an old version of Fedora?)
This might be a complicated question but I just want to know what the best way to solve this issue is. Change libraries? Statically link? Compile on old distributions? Let me know what you think.
I've considered statically linking the library, but I'm unsure if that might cause licensing issues,
Yes.
very old distribution such as Ubuntu 12 or something, but I won't know how well that carries over to other distros
It doesn't (alpine linux). If you compile software, you have to run it with the set of libraries you compiled it against. Even if you compile on "very old distributions" there may be changes.
publish to many distributions
Choose the list of distributions and versions of these distributions you want to support. Tell users that you will support these distribution versions. (https://partner.steamgames.com/doc/store/application/platforms -> Steam only officially supports Ubuntu running Ubuntu 12.04 LTS or newer..).
Compile against every combination of distribution+version separately, and distribute your software separately for every such distribution version. For users convenience, create and share package repositories for specific distribution package manager with your software. On https://www.zabbix.com/download there are only so many combinations to choose from. Interest yourself in CI/CD in docker virtualized environments. I like gitlab.
Or alternatively distribute your application with all dependent shared libraries. Bundle it all together with the operating system and distribute in a form of a docker image or a qemu/virtualbox virtual image. Or distribute with just shared libraries files with a wrapper around LD_PRELOAD. Just like steam does. Install steam on your system, and see what happens in ~/.steam/steam/ubuntu12_64.
And hire a layer to solve the licensing issues.
I am using a shared C library on Linux that is distributed in binary form. The problem is that the dependencies are set to require exactly the versions available on the development machine. For example, each release requires the (at the time) latest glibc and only the exact version of libreadline on their system.
I have contacted the developers and they don't know what to do about this. As far as I can tell, they are not consciously using the latest features, so the library should continue to work with older dependencies. I think they are using gcc on Linux, but they are also using a complex make system to control other compilers to build for Windows and Unix.
How and to what extent can you manage the build process so that a library requires dependencies just of a sufficient version and will also accept later versions?
This was a related question.
Edit: To be clear, I want to know how to build programs so they will accept dependencies with a specific version number or later numbers. Whether the developers compile it or I do, I want to be able to distribute a binary that does not require exactly the versions of dependencies present in the build environment.
Edit 2: After rephrasing the question, I realized this has been covered many times before. Some of the best Q&A:
Deploying Yesod to Heroku, can't build statically
Compile with older libc
Linking against an old version of libc
How can I link to a specific glibc version?
It's not very confidence inspiring. They should be building on a stable baseline release, it could just be a virtual install. Some versions of Linux, copy a build environment so packages aren't linked to updated library versions.
The openSUSE build service, lets devolopers build binary packages, for a wide variety of http://openbuildservice.org/about/
IIRC readline is a GPL program and checking at http://cnswww.cns.cwru.edu/php/chet/readline/rltop.html#Availability suggests it is GPL v 3 so they may be in violation of the GPL, if they are using libreadline functions and should provide you with the source to their library. I am not sure if you are meaning rpm/apt package dependencies, or their library is actually calling libreadline.
You can always extract files from rpm or apt packages, if necessary so avoiding software manager issues, caused by poor packaging.
Sorry if this is an obvious question, but I've found surprisingly few references on the web ...
I'm working with an API written in C by one of our business partners and supplied to us as a .so binary file, built on Fedora 11. We've been testing out the API on a Fedora 11 development machine with no problems. However, when I try to link against the API on our customer's target platform, which happens to be SuSE Enterprise 10.2, I get a "File format not recognized" error.
Commands that are also part of the binutils package, such as objdump or nm, give me the same file format error. The "file" command shows me:
ELF 64-bit LSB shared object, AMD x86-64, version 1 (SYSV), not stripped
and the "ldd" command shows:
ldd: warning: you do not have execution permission for `./libuscuavactivity.so.1.1'
./libuscuavactivity.so.1.1: /usr/lib64/libstdc++.so.6: version `GLIBCXX_3.4.9' not found (required by ./libuscuavactivity.so.1.1)
[dependent library list]
I'm guessing this is due to incompatibility between the C libraries on the two platforms, with the problem being that the code was compiled against a new version of glibc etc. than the one available on SuSE 10.2. I'm posting this question on the off chance that there is a way to compile the code on our partner's Fedora 11 platform in such a way that it will run on SuSE 10.2 as well.
I think the trick is to build on a flavour of linux with the oldest kernel and C library versions of any of the platforms you wish to support. In my job we build on Debian 4, which allows us to officially support Debian 4 and above, RedHat 3,4,5, SuSE 10 plus various other distros (SELinux etc.) in an unofficial fashion.
I suspect by building on a nice new version of linux, it becomes difficult to support people on older machines.
(edit) I should mention that we use the default compiler that comes with Debian 4, which I think is GCC 4.1.2. Installing newer compiler versions tends to make compatibility much worse.
Windows has it problems with compatability between different realeases, service packs, installed SDKs, and DLLs in general (DLL Hell, anyone?). Linux is not immune to the same kinds of issues.
The compatability issues I have seen include:
Runtime library changes
Link library changes
Kernel changes
Compiler technology changes (eg: pre and post EGCS gcc versions. This might be your issue).
Packager issues (RPM vs. APT)
In your particular case, I'd have them do a "gcc -v" on their system and report to you the gcc version number. Compare that to what you are using.
You might have to get hold of that version of the compiler to build your half with.
You can use Linux Application Checker tool ([1], [2], [3]) in order to solve compatibility problems of an application between Linux distributions. It will check your file formats and all dependent libraries. It supports almost all popular Linux distributions including all versions of SuSE and Fedora.
This is just a personal opinion, but when distributing something in binary-only form on Linux, you have a few options:
Build the gamut of .debs and .rpms for every distro under the sun, with a nominal ".tar.gz full of binaries" package for anything you've missed. The first part is ideal but cumbersome. The latter part will lead you to point 2 and 3.
Do as some are suggesting and find the oldest distro you can find and build there. My own opinion is this is sort of a ridiculous idea. See point 3.
Distribute binaries, and statically link where ever you can. Especially for libstdc++, which appears to be your problem here. There are seemingly very many incompatible versions of libstdc++ floating around, which makes it a compatibility nightmare. If you can't link statically, you can also put *.so files alongside your binary, and use stuff like LD_PRELOAD or LD_LIBRARY_PATH to make them link preferentially at runtime. Note that if you take this route you may have to comply with LGPL etc. since you are now distributing other people's work alongside your project.
Of course, distributing your project in source form is always preferred on Linux. :-)
If the message is file format not recognized then the problem is most likely one mentioned by elmarco in a comment -- namely, different architecture. It might (I'm not sure) be a dynamic linker version mismatch, but that would mean the .so file was built with an ancient dynamic linker. I do not believe any incompatibility in libc could cause this -- they could cause link failures and runtime problems (latter very rarely), but not this.
I don't know about Suse, but I know fedora likes to stay on the bleeding edge. So you may very well be right about library versions. Why don't you ask and see if you can get the source code and build it on your Suse machine?
I want to learn C language (is this something good ?) and i didn't know from where i can download the language to my PC ?
and are this FREE or must pay for ?
Is C a good language? Definitely. Is it the best first language? Depends.
If you are using Windows, you can download Visual C++ 2008 Express Edition SP1 from Microsoft for free.
On Ubuntu, just run
sudo apt-get install build-essential
On Mac OS X, install Xcode from Snow Leopard/Leopard DVD (or download the latest version from Apple developer Web site)
There are quite a few free C compilers for the PC.
As seen above, MS Visual Studio comes in a free version.
However, most introductory C programming materials will work best in a unix-like environment. Two options for such an environment are:
Cygwin, which provides a unix-like environment that can be installed over a windows system.
MinGW32/MSYS, which natively ports GCC and some unix-like development tooling onto Windows, allowing you to use GCC to build native Win32 apps.
For learning you might be better off running a native unix/linux environment. If you already have Windows and don't want to uninstall or dual-boot you can run this under a VM. Several free hypervisors are available that will let you do this.
If you want to use a different development environment you could try Eclipse.
Just go to this link and look for Eclipse IDE for C/C++ Developers (79 MB).
http://www.eclipse.org/downloads/
There is a free compiler called gcc that will compile C code. On Mac OS X and Linux you probably already have it, try typing gcc at a command prompt.
On Windows, you can still use gcc, but you need to use either Cygwin or Mingw.
Or if you want to use an IDE and Microsoft's C compiler you can get a free version of Visual Studio here.
You can use Dev C++ . Very decent tool for beginners and intermediates.
OK (all free):
For Windows
- there is Visual C++ Express
- MinGW (and is command-line based)
You will need the MS Platform SDK as well.
Linux/Sun
- GCC (there are a number of ways to get this distro depending)
OS X
- Apple's Developer Tools (Xcode and others)
It is definitely free to learn and program C, but the answer to your first question "is this something good ?" depends on what your goals are. C is a very good language for some things, but not everything.
System programming is almost always done in C, along with network programs and some applications. C is also the basis for most modern programming languages you will work with, so learning the C syntax can be applied as you go about learning other things. However, if you are looking to make a interactive webpage, you might want to learn PHP. If you are looking to make a desktop application with a GUI, you might want to learn Java.
If you want to just get a start learning about programming, C can help you with that. If that's what you want to do, and dont care much about application right now, I suggest you go to the bookstore and just find a book on learning C for beginners. It should have a CD in the back with a compiler (probably visual studio), and should get you on your way.
This is a an excellent reference of free compilers for many systems.
http://www.thefreecountry.com/compilers/cpp.shtml
Intel provides free non-commercial compilers for Linux. The download includes the excellent Intel debugger & profiler. The free license can be summed up in two points:
My use of software products is for personal non-commercial purposes.
I understand that technical support will be provided by community self-help and user forums (via the Software Support link above), but cannot get committed support with a non-commercial license.
For the projects I work on, I personally prefer Intel Compilers over GNU... Intel seems to do a better job of optimization.
On Windows, I'll suggest Dev CPP. This is free an a very good product. It is also easier for the newbies to learn. I used it a lot. You can download the latest from
http://www.bloodshed.net/devcpp.html
If in Linux, there should be gcc. Use any editor of your choice( In my case vim). Just type vim filename.c in the terminal. This should bring the editor. press 'i' and write in the code. then press 'Esc' followed by ':' and x (This will save the file and exit the editor.
Now type gcc filename.c at the terminal. this should compile it. Now enter ./a.out to execute it.
If you wanted a "portable" compiler, Tiny C Compiler is a decent compiler that you can take with you on a USB stick - it's only a single .exe file or a single folder IIRC. It is cross platform as well, but the biggest downsides are that the warnings are lacking and that it's optimization isn't as good as the bigger compilers out there.
Nonetheless, it's a decent compiler to "play around with" if you don't want to install Visual Studio or Cygwin on Windows.
I think you need to be clear about the distinction between C and C++ before you decide what to do.
On Windows, try either Digital Mars C and C++ compilers or Open Watcom C and C++ products
About.com maintains a large list of c compilers for windows at http://cplus.about.com/od/glossary/a/compilers.htm
I been looking into Cygwin/Mingw/lcc and I liked to be able to compile perl native C extensions on my windows(preferably under cygwin) and then run them on Solaris and HP unix without any further fuss, is this possible?
This all stems from my original perl cross-platform question here.
(This is a very old question, but missing some useful info --
I've personally done this for Solaris (SPARC & x86), AIX, HP-UX and Linux (x86, x64).)
Getting C++ cross-compiled is much harder than straight C.
HP-UX 32-bit PA-RISC is not supported because it uses SOM format instead of ELF and binutils doesn't (and likely won't ever) support SOM. In other words, you can only cross-compile 64-bit PA-RISC. (Requires PA-RISC 2.0 chip.)
I would go with mingw instead of cygwin, if you can. Cygwin introduces a lot of file permission headaches and cygwin1.dll dependencies that can be troublesome. If possible, however, build on linux. Everything will be much faster because all the tools and scripts you're running are designed for an environment where exec and stat are fast operations. Windows + NTFS is not that environment.
Start with the crosstools script, but be prepared to spend a lot of time on this.
Try with the very latest gcc/binutuils first, but if you can't overcome problems try dropping back to older packages. E.g. for Power3 (AIX) gcc 4.x series cross compiler generates bad code, 3.x is fine.
When copying native libs and headers make sure you are copying from the oldest machine you're likely to run on. Copying a new libc means your code won't run on any machine with an older libc.
When copying native libs and headers you probably want 'tar -h' to turn symlinks into actual files, also watch that on Solaris some requisite crt object files are buried in a cc directory, not under /usr/lib
Cross-compiler are very hard to setup and get working correctly.
Consider that (the people at) NetBSD have to put in a huge amount of work to get cross-compiling to work, and they're running the same OS, just different architectures.
You'd have to, at least, copy all the headers from the other OSs to Windows, and get a cross-compiler, linker etc for the target OS/architecture.
Also that may well not be possible - perl and shared libraries may be compiled with a native/non-gcc compiler which won't be available on Windows at all.
I agree with Douglas, that getting a cross compiler up and working is very hard to do. This is generally, your choice of last resort. If you are boot strapping, or making a binary for an embedded device, then often cross-compiling is your only option. You should be comfortable compiling your own gcc under Cygwin before considering cross compiling. To cross compile, you need to build a gcc to run under windows, but which will create binaries for your execution platform. Sample instructions for doing this can be found here.
Perhaps you are wanting to cross compile because you don't have root and/or can't compile on your target platform. For example, I had a hosting provider which ran Redhat Linux. I could run Perl CGI scripts, and associated modules, but I could not compile on the target machine, and an libraries I built had to exist in my own directory.
To solve this, I could have attempted to cross compile for my target platform, but instead, I decided to setup a similar host inside a VM on Windows. From within Cygwin, you can create a script which ssh's into your VM, copies your source, and does a full configure/build. The last step was to deploy the binary artifact onto my hosted system.
I've successfully had both Solaris 10 and Open Solaris running within a VM on Windows. Unfortunately, you might have a harder time running HPUX under a VM.
Why don't you have a read up on "Grand Unified Builder" (http://lilypond.org/gub/ and http://valentin.villenave.info/The-LilyPond-Report-11 (section #4))
I don't know how it works, but GUB allows the Lilypond developers to compile for about 11 platforms on a linux box.
Compile on Windows then use Wine to run them on any *nix. It works well most of the time.
No, this isn't possible at the binary level. There are so many differences at binary level between the various OSes and CPUs.
But what you can do is make the your C extensions source compatible so that it can compile to different platforms. C was designed as a "portable assembly language". As long as you stick with routines that are cross-platform, then they will usually work the same. You'll still need to test because there could be bugs that exists on particular platform.
This can't be done ... but is it that much of a hassle to recompile the code under Solaris or HP?