This function is called by setup_locker() to initialize and
re-initialize a locker directory. We call it reset_locker because it is
expected that the locker space is created once and then repeatedly
reset and simulations are run and re-run.
Arguments
- where
The full path to the locker.
- pattern
A regular expression for finding files to clear from the locker directory.
Details
If user confirmation for reset was previously requested via setup_locker()
or config_locker(), then the user will be asked to confirm prior
to reset.
For the locker space to be initialized, the where directory must not
exist; if it exists, there will be an error. It is also an error for
where to exist and not contain a particular hidden locker file name
that marks the directory as established locker space.
NOTE: when the locker is reset, all contents are cleared according
to the files matched by pattern. If any un-matched files exist after
clearing the directory, a warning will be issued.