Lockfiles are a *nix trope that have no enforced usage pattern. Many systems provide a standard location in the filesystem, such as the /var/run tree, for lockfiles to simplify permissions management. However, the location of a lockfile is irrelevant.

In the case of init.d scripts, the lockfile is usually used by the script to determine whether the service is running already. Starting a service checks for the lockfile and fails if...