On z/OS and VOS3, the following standard routing and description codes are used.
| Routing Code | Use |
|---|---|
| 1 | Action |
| 2 | Operator Information |
| 9 | Security |
| 11 | Programmer Information |
| Descriptor Code | Use |
|---|---|
| 2 | Action |
| 4 | System Status |
| 7 | Task Related |
Messages with descriptor code 2 are retained on operator consoles until TDP deletes them, unless the system's action message retention facility is disabled (using the system K M,AMRF=N command).