The ISSUE ERASEAUP command is used to erase all unprotected
fields of a 3270 buffer, by the following actions:
- All unprotected fields are cleared to nulls (X'00').
- The modified data tags (MDTs) in each unprotected field are reset to zero.
- The cursor is positioned to the first unprotected field.
- The keyboard is restored.
The WAIT option of the ISSUE ERASEAUP command ensures that the operation
has been completed before control is returned to the application program.