how package dependencies version name check work?

Aquarius Power

5/23/23, 5:09 PM

I think what is not clear is the version naming check.
For ex.:

$ sudo apt install libsdl2-dev
libsdl2-dev : Depends: libasound2-dev but it is not going to be installed
$ sudo apt install libasound2-dev
libasound2-dev : Depends: libasound2 (= 1.2.2-2.1)
$ sudo apt install libasound2
libasound2 is already the newest version (1.2.2-2.1ubuntu2).

So, why version "1.2.2-2.1" differs from "1.2.2-2.1ubuntu2" ?
I mean, is apt install looking for "1.2.2-2.1" and when it checks about the package "1.2.2-2.1ubuntu2" it is unable to match or something else is happening ?
Should I remove the package version "1.2.2-2.1ubuntu2" and try to find and install it versioned like "1.2.2-2.1" ?

Could I use some trick to let apt install accept "1.2.2-2.1ubuntu2" as if it was the probably different package named "1.2.2-2.1"?
And finally, is package version "1.2.2-2.1" really different from "1.2.2-2.1ubuntu2"?
If not, could I just repack "1.2.2-2.1ubuntu2" as "1.2.2-2.1"? but how? (tho I found that many packages depend on the specific "1.2.2-2.1ubuntu2" and it would be too much trouble to change them all, in case it could work of course)

0 + 0

apt

dependencies

user535733

5/23/23, 6:06 PM

Look at the comparison operator: `=`. The version string match must be *exact*, no different characters, no additional characters, no fewer characters.

Aquarius Power

5/29/23, 1:43 AM

ah.. anyway the real problem that made me ask this is that I dont get why SDL2 dev is impossible to be installed, the dependencies are weird! if I really try, it will ask to uninstall a lot of packages and that makes no sense. I dont get also why other ppl are not having this problem (or at least not talking about it as I cant find a solution on google).

user535733

5/29/23, 1:59 AM

Check your sources: Do you have focal-updates enabled? Does an `apt update` work properly?

Aquarius Power

6/23/23, 2:02 AM

@user535733 solved here: https://askubuntu.com/questions/1389872/why-it-is-impossible-to-install-libsdl2-dev-on-ubuntu-20-04-or-is-there-some-wa?noredirect=1#comment2402319_1389872 , thx!

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: how package dependencies version name check work?

TH: การตรวจสอบชื่อเวอร์ชันการขึ้นต่อกันของแพ็คเกจทำงานอย่างไร

RO: cum funcționează verificarea numelui versiunii dependențelor pachetului?

RU: как работает проверка имени версии зависимостей пакета?

VI: kiểm tra tên phiên bản phụ thuộc gói hoạt động như thế nào?

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