Saving objects
On shutdown, PPS always saves any modified objects in a persistent filesystem. You can also force PPS to save an object at any time by calling fsync() on the object.
When PPS saves its data in a persistent filesystem, it saves each object in its own file, in a directory hierarchy that reproduces the hierarchy of the PPS object tree. For example, with a default configuration, the PPS object /pps/example/object1 is stored at /var/pps/example/object1.
The default location for the PPS directory is /var/pps. You can use the PPS -p option to change this location.
- It's possible to edit the persistent version of the PPS files. If security is important to your system, you should have PPS save its data in an encrypted filesystem.
- You can set object and attribute qualifiers to have PPS not save specific objects or attributes.
Changing the directory for persistent storage
The root PPS object tree (/pps by default) may look something like this:
# pwd
/pps
# ls -1F
accounts/
applications/
qnx/
qnxcar/
servicedata/
services/
system/
#
PPS populates its root object tree from the persistence tree (/var/pps by default), where the objects and attributes that you want to persist are stored.
- Create your own persistence directory (e.g.,
mkdir /myobjects). - Start the PPS service from a different mountpoint (e.g., /fs/pps) and
specify your new persistence directory:
pps -m /fs/pps -p /myobjects