Enables the target, opens and writes to the file in append mode.
+ If the target already exists and is a directory, the traces will be
+ written to files (one per process) underneath the given directory. They
+ will be named according to the last component of the SID (optionally
+ followed by a counter to avoid filename collisions).
+
`af_unix:[<socket_type>:]<absolute-pathname>`::
Enables the target, opens and writes to a Unix Domain Socket