override(P, D) Use the version of package P in directory D/P instead of the one in /pkg/P.
override alters the behaviour of the include_pkg and import_pkg procedures, and must be executed prior to any such calls to have an effect.
To help ensure that the public repositories are consistent, m3ship will refuse to install any package built using overrides.
When the -override option is specified, cm3 looks for a file named m3overrides in the src directory and, if one exists, executes it immediately prior to executing m3makefile. By keeping all override calls in an m3overrides file and not in an m3makefile, you can build both private and public versions of packages without editting any files.
The overrides in effect when a package was built are automatically carried forward into importers of the package, so there is no need to restate the complete set of overrides at every level, only of those packages that are directly imported into a given package.
There is a pre-declared variable, WDROOT, that defines the conventional location of a user's private package repository. (see \ref{VAR-sec}).