The following descriptions are general, and should be interpreted in the context of the specific function and circumstances.
| ST_OK | The function executed without error. |
| ST_ERROR | An error occurred. |
| ST_NO_TASK | A required task does not exist. |
| ST_NO_MSG | There is no message available. |
| ST_WOULDBLOCK | This action would block, and is not permitted. |
| ST_INTR | An interrupt occurred. |
| ST_FULL | The queue is full. |
| ST_LOCKED | A Cascade DataHub point is locked. |
| ST_SECURITY | The security level is insufficient. |
| ST_NO_POINT | A required Cascade DataHub point does not exist. |
| ST_INSIG | A change in a Cascade DataHub point's value is insignificant. This is not really an error, but a notification that no exception will be generated by the datahub. |
| ST_UNKNOWN | There is an unknown error. |
| ST_NO_QUEUE | A target task has no queue, or qserve is absent. |
| ST_CMD_SYNTAX_ERROR | The command was not found, or there was a syntax error. |
| ST_REPLIED | The reply was complete. |
| ST_WRONG_TYPE | The type of a point or variable was wrong. |
| ST_TOO_LARGE | A value to be written to memory is larger than the available buffer. |
| ST_NO_MEMORY | There is insufficient memory available. |
| ST_OLD_DATA | Time-significant data is out of date. |
| ST_TIMEOUT | A timeout occurred in poll mode. |