What package do i need to install for using routing sockets?

Please note, you DO NOT need to make in that folder "libroute"

See the Document:

cd ../libroute # only if your system supports 4.4BSD style routing sockets
make           # only if your system supports 4.4BSD style routing sockets

cd ../libxti   # only if your system supports XTI
make           # only if your system supports XTI

Linux is not BSD style routing, just go to ../intro and build examples~!

That is a BSD-specific API, and linux doesn't support it. The equivalent functionality (not source-compatible) is provided by the netlink socket family. "man 7 netlink" should get you started, but you're likely going to need to do some porting work.

I'm not on a machine where I can do this right now, but perhaps I can still help. If your distribution uses yum (e.g. RHEL):

yum provides if_dl.h

Or if you use apt (e.g. Ubuntu/Debian):

sudo apt-get install apt-file
sudo apt-file update
apt-file search if_dl.h

If apt-file is already installed, the first step won't be necessary, and I can't remember for sure if the second is. Also, I believe both package managers work both with filename and with full path.

Hopefully this will work for you or someone else reading this, and you'll get your answer!