Creates a separate thread and namespace, runs the installer in that thread with the new namespace, and returns when the thread completes or dies. It also creates a custodian (see Custodians) to manage the created thread, sets the exit handler for the thread to shut down the custodian, and explicitly shuts down the custodian when the created thread terminates or dies.

The get-dir-proc procedure is called if the installer needs a target directory for installation, and a #f result means that the user canceled the installation. Typically, get-dir-proc is current-directory. v

Similar to run-single-installer, but runs the setup process to install the archive file into directory as the PLaneT package described by spec. The user-specific documentation index is not rebuilt, so reindex-user-documentation should be run after a set of PLaneT packages are installed.

Similar to run-single-installer, but runs only the part of the setup process that rebuilds the user-specific documentation start page, search page, and master index.

Undoes the work of install-planet-package. The user-specific documentation index is not rebuilt, so reindex-user-documentation should be run after a set of PLaneT packages are removed.