[submodule "libc-database"]

• path = libc-database
• url = https://github.com/lieanu/libc-database.git

• path = libc-database
• url = https://github.com/lieanu/libc-database.git

so the change have any difference compared with before?

Well, if you click on the libc-database @ 4ebb57b on https://github.com/lieanu/LibcSearcher, you can only get a 404 error page. And if you clone this repo and run git submodule update --init --recursive , it will fail with the error Server does not allow request for unadvertised object. This PR is to solve this misconfiguration.

However, I didn't find out how to modify the commit id directly, so I deleted this submodule and added it again to fix this problem. And... .gitmodules is modified.

The real change that takes effect is "Submodule libc-database updated from 4ebb57 to 309334".

but there is another question:
when in libc-database:
use ./get: an erroe happen

Getting package location for ubuntu-vivid-i386
Failed to get package version
Getting
-> Location: ubuntu-vivid-i386-libc6
-> ID:
-> Downloading package
Failed to download package from ubuntu-vivid-i386-libc6

and when git clone libc-database directly, and then use ./get, there isn't the error.

If you go to see the Ubuntu support timeline, you will find that Canonical is still supporting 14.04 (Trusty), because it is a LTS (Long Time Support) version. However, 15.04 (Vivid) is no longer supported. If you still wanna download the libc of old versions, go to old-releases.ubuntu.com instead of security.ubuntu.com.

Well, it seems that the author of this repo forked libc-database himself (or herself?), and modified some code about 2 years ago. So I guess that his own forked repo is out-of-date for this change. The original libc-database has modified the get shell script and commented the command of downloading libc of some old Ubuntu versions (including vivid).

So, maybe, the best solution is to modify the get script and comment the out-of-date commands, or directly change the submodule url to the original libc-database instead of the old repo forked by the author.