currently the two utility functions in backup used to dump and restore the astdb are designed to be used together with ampbackup.php in such a way that they are not 'user friendly' for someone to use independently. The basically expect an argument which references a current backup set being saved/restored in a format that requires access that looks something like this (in the case of restoreadtdb):
$dump = file_get_contents("/tmp/ampbackups.".$argv."/astdb.dump");
where the argument is the date code of a backup tarball that has been exploded into /tmp in the give directory (or being saved there if dumpastdb where examined).
We need to modify these functions and the corresponding ampbackup.php, or otherwise add an option such that they can be easily run independently as a utility tool form the CLI without the expectation of the specific directory and naming structure assumed.