VMS Help CMS, DELETE, HISTORY, Description  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The DELETE HISTORY command deletes all or part of the library
    history. By default, CMS writes the deleted history records to
    a file named HISTORY.DMP in your current default directory. CMS
    cannot access this file as a history file.

    The DELETE HISTORY command does not delete the library creation
    history record.

    Whenever you delete some of the library history, CMS records two
    transactions. As with other commands that modify the contents of
    the library, CMS records the deletion transaction. In addition,
    CMS logs a REMARK transaction at the point that corresponds to
    the /BEFORE value. If you do not specify the /BEFORE qualifier,
    the default is /BEFORE=current-time. The REMARK transaction
    record includes the following remark: "PREVIOUS HISTORY DELETED".
    Both the REMARK and the DELETE HISTORY transactions are unusual
    transactions. When you use the SHOW HISTORY command, CMS
    identifies unusual transactions by displaying an asterisk (*)
    in the first column of the transaction record.