3270 terminal lock and unlock option
During IMS system definition, by using the TERMINAL and TYPE macros or Extended Terminal Option (ETO) logon descriptors, you can specify whether the application program or IMS should be responsible for unlocking the terminal keyboard and resetting the modified data tags.
If you select LOCK, the application
program unlocks the keyboard after it receives input. If you select UNLOCK, IMS controls the unlocking of the
keyboard. This option only applies to messages that bypass Message
Format Service (MFS) on output with a MOD name of DFS.EDTN.
If the application program terminates without unlocking the keyboard, you can unlock the keyboard by pressing the Reset key.
Attention: If the application has not terminated but is
slow in responding, do not press the Reset key and start entering
data, because the data might be lost when the application program
sends another output message to the terminal.