Messages

See Figure 8.13 for the derivation hierarchy of the Message events.

**Figure 8.13:** Messages
$\includegraphics{hdr/message.ps}$

See Figure 8.14 for the derivation hierarchy for error message type codes.

**Figure 8.14:** Error messages
$\includegraphics{dot/api_code.ps}$

Bill Pippin 2009-01-02