Symlink clarification needed (vi -> vim)

[Robert Ian Smit <robian@wanadoo.nl>]

I know that some programs react differently depending on how they
are called. When you create a symlink to a program, does the program
know that it was started by using a symlink?

For instance when I create a vi symlink to vim, will vim start up
normally or will it mimick vi?

If so, can I change this without going into config files for the
program?

I am asking this because I want to use (vim) vi on a non-Debian
system that does not create symlinks for this package or use an
alternatives system.

Bob