All signal functions are supported when the task is set up for signals, when it is running with the signal delivery key, and when its current program request block (PRB) is the same PRB as when the task was set up for signals. When this is not the case, some signal functions are not supported, or they function differently. Table 1 defines these signal functions.
The mvssigsetup columns in Table 1 describe a task that is set up with the mvssigsetup service. When a task invokes the mvssigsetup service, the current PRB is recorded for future signal delivery. When a task is set up for signals by mvssigsetup, signals are only delivered when the task's current PRB is the same PRB that called mvssigsetup.
| Service | Task mvssigsetup | Not signal delivery key | Task not mvssigsetup | ||
|---|---|---|---|---|---|
| The current PRB called mvssigsetup | The current PRB did not call mvssigsetup | The current PRB dubbed the task | The current PRB did not dub the task | ||
| BPX1ALR | RV=Seconds | Abend | RV=Seconds | RV=Seconds | Abend |
| BPX1KIL | RV=0 | RV=0 | RV=0 | RV=0 | RV=0 |
| BPX1MSD | RV=0 | RV=0 | RV=0 | RV=-1 | RV=-1 |
| BPX1MSS | RV=-1 | RV=-1 | RV=-1 | RV=0 | RV=0 |
| BPX1PAS | RV=0 | RV=-1 | RV=-1 | RV=0 | RV=0 |
| BPX1SEL | RV=0 | RV=-1 | RV=-1 | RV=0 | RV=0 |
| BPX1SIA | RV=0 | RV=-1 | RV=0 | RV=-1 | RV=-1 |
| BPX1SIP | RV=0 | RV=-1 | RV=0 | RV=0 | RV=0 |
| BPX1SLP | RV=Seconds | RV=Abend | RV=Abend | RV=Seconds | RV=Seconds |
| BPX1SPB | RV=0 | N/A | N/A | N/A | N/A |
| BPX1SPM | RV=0 | RV=-1 | RV=0 | RV=0 | RV=0 |
| BPX1SSU | RV=0 | RV=-1 | RV=-1 | RV=0 | RV=0 |