This question is posted from time to time. We had the same problem in our AIX boxes but we didn’t want to cycle our interfaces continuously. We turned off the “save inbound/outbound messages” feature and created tclprocs to save the messages with their metadata (with the same format in the .msg and .idx files).
Now we can use hcismat or any other tool (grep, cat, more, etc.) to open the files (as read only) while receiving messages. So far we haven’t experienced any loss of data. I recommend this solution only if you need to see the content of those files on a regular basis.
Carlos
