PELs: Document _PID as an AdditionalData keyword
When one uses the new `Create` D-Bus API to create an event
log that will be converted into a PEL, the log-manager daemon
will not know the PID of the creator, unlike when the 'commit'
or 'report' shared library APIs are used.
Document this method for allowing the creator to pass in their
PID, which they can find with getpid(), if they want their PID
in an event log and in the corresponding PEL.
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I0fadaed301bcd87de1d4395f6c6ec0baacfe0b97
diff --git a/extensions/openpower-pels/README.md b/extensions/openpower-pels/README.md
index 5fb5e8e..1c6b1a3 100644
--- a/extensions/openpower-pels/README.md
+++ b/extensions/openpower-pels/README.md
@@ -23,6 +23,24 @@
The code will assign its own error log ID to this PEL, and also update the
commit timestamp field to the current time.
+#### _PID
+
+This keyword that contains the application's PID is added automatically by the
+phosphor-logging daemon when the `commit` or `report` APIs are used to create
+an event log, but not when the `Create` D-Bus method is used. If a caller of
+the `Create` API wishes to have their PID captured in the PEL this should be
+used.
+
+This will be added to the PEL in a section of type User Data (UD), along with
+the application name it corresponds to.
+
+The syntax is:
+```
+_PID=<PID of application>
+e.g.
+_PID="12345"
+```
+
## The PEL Message Registry
## D-Bus Interfaces