I need to determine whether a print job succeeded for the following two printer models. #1 is fine, #2 is not.

Zebra ZT230 with firmware V72.20.10Z (Link-OS 5)
Zebra S4M with firmware V58.17.12Z

The printer application is a Windows C# program.

The ZT230 printer print job success can be checked by reading the total number of labels printed before and after sending the print job (! U1 getvar "odometer.total_label_count"). This command does not seem to be supported for the S4M printer as it returns "?".

The ~HS Host Status command is being used to check whether the printers are ready to print. I have seen it suggested that reading the Number of Formats in Receive Buffer via the ~HS Host Status command will tell you when a print job is complete, but the S4M printer is so slow in responding to this command that the value is almost always 0 when printing single labels, so that does not give any real information.

We have previously used the SNMP alert for PQ JOB DONE to determine that the S4M printer print job has succeeded, but we would like to switch from the alert callback mechanism to a printer query if possible.

Is there an equivalent command similar to the odometer.total_label_count reading that will definitely tell you that an S4M printer has completed a print job? Thank you for any help!