SAP CALL EVENT BLOCKS

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Call Event Blocks
Event blocks are processing blocks in an ABAP program that are executed when the associated event occurs in the ABAP runtime framework. In two cases, such events can be raised programmatically and the event blocks, if implemented, can be called:

Using the statement SET USER-COMMAND in classic list processing

Using the statement PUT in logical databases
Both statements are effectively obsolete. For more information, see the relevant sections.