A major return code of 81 indicates a serious error that affects the device or session.
This includes hardware failures that affect the device, communications line, or communications controller. It also includes errors due to a device being disconnected or powered off unexpectedly and abnormal conditions that were discovered by the device and reported back to the server. Both the minor return code and the accompanying message provide more specific information regarding the cause of the problem.
Depending on the file type, the program must either close the file and open it again, release the device and acquire it again, or acquire the session again. To reset an error condition in a shared file by closing it and opening it again, all programs sharing the open data path must close the file. In some cases, the message might instruct you to reset the device by varying it off and on again. It is unlikely that the program will be able to use the failing device until the problem causing the error is found and corrected, but recovery within the program might be possible if an alternate device is available.
Some of the minor return codes in this group are the same as those for the 82 major return code. Device failures or line failures might occur at any time, but an 81 major code occurs on an I/O operation. This means that your program had already established a link with the device or session. Therefore, the program can transfer some data, but when the program starts from the beginning when it starts again. A possible duplication of data might result.
Message numbers accompanying an 81 major code might be in the range that indicates either an I/O or a close operation. A device failure on a close operation might be the result of a failure in sending the final block of data, rather than action specific to closing the file. An error on a close operation can cause a file to not close completely. Your error recovery program should respond to close failures with a second close operation. The second close will always complete, regardless of errors.