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CDE — Making Linux Portability Easy
ihaque writes "A Stanford researcher, Philip Guo, has developed a tool called CDE to automatically package up a Linux program and all its dependencies (including system-level libraries, fonts, etc!) so that it can be run out of the box on another Linux machine without a lot of complicated work setting up libraries and program versions or dealing with dependency version hell. He's got binaries, source code, and a screencast up. Looks to be really useful for large cluster/cloud deployments as well as program sharing. Says Guo, 'CDE is a tool that automatically packages up the Code, Data, and Environment involved in running any Linux command so that it can execute identically on another computer without any installation or configuration. The only requirement is that the other computer have the same hardware architecture (e.g., x86) and major kernel version (e.g., 2.6.X) as yours. CDE allows you to easily run programs without the dependency hell that inevitably occurs when attempting to install software or libraries. You can use CDE to allow your colleagues to reproduce and build upon your computational experiments, to quickly deploy prototype software to a compute cluster, and to submit executable bug reports.'"
Making applications portable is handy for doing things like running them from a USB stick. It also makes backup much more convenient.
Copy the program and its data in one shot, carry it with you, and use anywhere.
Windows apps are ahead of the game on this one:
http://portableapps.com/
"This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
One method is to have a tool for interrogating the API version and also testing the API against some set of tests that relate to the application being installed. You'd then apply the following:
This should keep redundancy to a minimum. There will be some, since there's nothing in this to collaborate between apps using this method, but it's a start.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
That's probably another use, but I really don't think that's the main place where it'd be useful. I DREAM of being able to just download an application archive, extract it *anywhere I want*, and just run it. Just use it, without having to worry. Any application - not the apps (and versions) that some distribution maintainer has gotten around to porting to my flavor.
No, solving dependency hell is far worse today. Building from source back in tarball only days you had problems if version W of library X was not installed. Building from source today you have that along with issues if your distro of choice does not have version W of library X in the repository along with actually having version W of library X that you built from source installed but your package manager refusing to install things dependent on it because it refuses to acknowledge anything's existence outside its list of installed packages.
You also have issues like cpan which is currentish vs your distro's package manager which is usually anything but.
If it weren't for checkinstall I'd seriously consider LFS over package management in situations where I was constantly having to build things from git/cpan/etc... And I'd probably have a huge dent in my desk from where I constantly banged my head instead of the only moderately sized one I have now.
Violence is like duct tape. If it doesn't solve the problem, you didn't use enough.
Sorry if topic sounds a tad personal, but hey...
> The real problem is that Linux distributions, taken together or individually, presents developers with too many completely unnecessary choices as to where essential library files can be put, and also, there is no standard version naming and locating convention.
Do you need it to boot? Prefix is / /usr /usr/local or /opt /import/x86 etc is a good place
Do you need it after boot? Prefix is
Do you want to install custom stuff that is not handled via the system's default software handling solution? Prefix is
Do you want to install into home dir? Prefix is ~/local or ~/opt
If you are in a heterogenous environment with shared home between lots of architectures etc,
This leads to clean & clear separation of software after a system people poured a lot of thought into. Is it easy to grasp at first sight for someone used to Windows? No. But that is _not_ the priority. Sorry, it's not. People writing code need to learn how the language works. Why shouldn't they learn how to system works?
> Package managers are a complex solution to a problem that need not have existed in the first place, if it was realized that unnecessary choice is deadly dangerous, in the world of large-scale software interoperability.
Yeah, cause grabbing random downloads of .bat, .exe, .msi, .whatnot turned out to be awesome. Especially the integrated updates. Oh, what's that? Everyone is implementing their own system leading to dozens of parallel update mechanisms on a single machine? Now _that_ is efficient! And the programs that don't have an update routine? Simple, just write them bug-free, without holes and a complete feature set in 1.0!
> There does not need to be any choice for where on a file system a given application or a given library should be located.
That is true if you consider every machine to be an island. Unix thrived and continues to thrive cause you can create huge shared environments with almost no work.
> That should be completely determined by the app or library name, version (using a standard versioning scheme), variant (using a standard variant naming scheme), and origin person-or-organization, using a standard organization identifying scheme.
My custom mplayer is in /usr/local/mplayer. My custom git is in /usr/local/git. My custom vim is in /usr/local/vim. I can delete any of those and remove the program, along with all its libraries and whatnot, with one single rm. /usr/local for stuff, again... It's their problem, same as if they did not know how to open() a file.
If devs simply don't know that they should default to
> It goes without saying that there should also be a standard globally unique URI for such libraries and apps (including the unique name, version, variant, origin identification).
No. No. No. This breaks any and all assumptions about being able to install different versions of stuff for different reasons. Use prefixes and use LD_PATH, etc.
> So there should be no choice about where on the internet to get it (except for the choice involved in a standard mirroring URI scheme), and
no choice about where to put it.
Maybe you are too young to have seen this yourself, but after a few years, most URLs are dead. With gittorrent, ideally with a DHT sprinkled on top, this might change in the longer run, but what if the next VCS that whoops git's ass comes along? Static information on the internet is mostly a myth. (Also, git would need to get rid of SHA1 for fully automated code distribution, imo)
> With this discipline, obviously needed in today's universe of code, all such package management, as well as dependency acquisition and installation, could be managed by a single unified and incredibly simple automated package manager; call it the