Arm versions, cross compiling etc


4 posts
by texy » Tue May 01, 2012 5:52 pm
I"m confused about the arm versions of software running on the pi.
If for example I am running Linux on my x86 laptop, the various softwares can be apt-get via the command prompt as long as they exist in one of the sources. I can then also apt-get those same softwares via the pi that also points to this same sources. What I don"t understand is doesn"t the softwares downloaded need to be compiled to run on the arm processor and not the x86 family. How does it know/work ? Clearly I"m missing something!
Cheers
Texy
"2.8inch TFT LCD + Touch screen" add-on boards for sale here :
http://www.raspberrypi.org/phpBB3/viewtopic.php?f=93&t=65566
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by texy » Tue May 01, 2012 5:53 pm
Wow 100th post too ;-)
"2.8inch TFT LCD + Touch screen" add-on boards for sale here :
http://www.raspberrypi.org/phpBB3/viewtopic.php?f=93&t=65566
50p goes to the Foundation ;-)
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by jamesh » Tue May 01, 2012 6:01 pm
There are actually different respositories of programs for each architecture. So in our case, Debian have compiled all the programs for Armv6 and put them online, as well as doing the same for x86 - and other architectures.  The apt-get program knows what architecture to search for, and grabs the right stuff.

This is one reason why Ubuntu dropped support for Armv6 - all the work involved in compiling all the programs for the repository, and supplying the servers to host it all. It's a very non-trivial amount of work as you can imagine.
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by texy » Wed May 02, 2012 6:06 am
OK, I see, its the apt-get command that sorts it out, even though it may point to the same package resource list address as the x86 versions of software.

Cool, cheers,

Texy
"2.8inch TFT LCD + Touch screen" add-on boards for sale here :
http://www.raspberrypi.org/phpBB3/viewtopic.php?f=93&t=65566
50p goes to the Foundation ;-)
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