https://www.ibm.com/docs/en/ims/15.4.0?topic=dfs3300i-dfs3261i
IMS 15.4 - IMS messages - DFS3261I
WRITE AHEAD DATA SET NOW ON ddname
imsmessages
https://www.ibm.com/docs/en/ims/15.1.0?topic=dfs3300i-dfs3261i
IMS 15 - IMS messages - DFS3261I
WRITE AHEAD DATA SET NOW ON ddname
imsmessages