Filtering notifications

You can filter PPS notifications based on the names of attributes, the values of attributes, or a combination of the two.

To filter notifications, use the following syntax:


where attrspec is an attribute specification consisting of either an attribute's name or an expression specifying an attribute's value. If you want to be notified when the attribute is deleted, add a minus sign (-) before its name:


The syntax for specifying an attribute's value is:


where attr is the attribute's name, operator is the operator used to determine the threshold for triggering notifications, and value is the value to compare to.

Supported operators are:

If you specify only an attribute's name, PPS notifies you of any updates where an attribute with that name is set. If you specify a name, operator, and value, PPS notifies you of any updates where the named attribute is set to a value that matches the given operator and value expression.

In both full and delta modes, the file descriptor will get notifications if any of the attribute specifications match:

In the following examples, the name of the object being opened is "objname":