opkg print-architecture - how is it useful ?

tjoseph1

Hi all,

Can someone tell me the use of "print-architecture" option..

It is listed under " Informational Commands" of opkg --help as:
print-architecture => List installable package architectures

When I run it, I get the following:

root@Omega-745F:/tmp/# opkg print-architecture
arch all 1
arch noarch 1
arch mipsel_24kc 10

Thanks ..

crispyoz

@tjoseph1

When you create anipk there are a few files you need to create, one of which is the control file where you enter things like dependencies and versioning information, plus the supported architecture. Since opkg is used on OpenWrt and OpenWrt supports multiple processor types, features available on one architecture may not be available on another. If there are no architectural dependencies you enter "all" in your control file, otherwise you can list the supported architectures. The mipsel_24kc is the architecture used by the Omega2 series, MIPS architecture. 24K family.

I'm not 100% sure about the intent of "noarch" however when I was first learning to make ipks i missed the architecture entry in my control file and so when I tried to install my package file from the repository the package was not shown. I determined that the cause was that in /etc/opkg.conf I had listed arch mipsel_24kc only. Therefore only packages created for this architecture would be shown, packages with with "all" would also be shown. I added "noarch" to my opkg.conf and my package was then visible. So maybe it is a legacy thing where architecture was not used, or is it a feature to allow you to include packages where no specific architecture has been specified.

The numbers after the architecture are the index, so if you have a package for a range/family of a particular chip you may make that a higher number than the same package set for a specific chip that may be covered by that range. This allows you to create a specific package for a specific chip that may differ from its family in some way that would require a change in your package specific to that chip. The higher the number, the lower in the search tree.

Not a great explanation but I hope it make sense.

tjoseph1

@crispyoz :

Thanks ..yes, it makes sense to prepare packages when lot of platforms are to be supported.