VMS Help SORT, Specification File Qualifiers, /CONDITION, Full Description  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    A specification file can be used to change the relative order of
    a record or to alter the contents of certain fields of a record.
    You must first use a /CONDITION qualifier to define a conditional
    test. Once you define a test using a /CONDITIONAL qualifier, you
    can use that same test with a /KEY or /DATA qualifier to change
    the order of record. You can also use the test with an /OMIT or
    /INCLUDE qualifier to change the contents of a record.

    If you want to change the order of records in the output file,
    first specify a condition name with a /CONDITION qualifier and
    set up a test for what meets that condition. Then, specify the
    relative order with a /KEY qualifier of the form:

    /KEY=(IF condition-name THEN value ELSE value)

    You can use any values to specify the relative order of the
    records.

    The /CONDITION qualifier also permits you to change the contents
    of a field in the output records. First specify a condition name,
    and then set up a test for what meets the condition. Specify the
    contents you want in the field in a /DATA qualifier of the form:

    /DATA=(IF condition-name THEN "new-contents" ELSE "new-contents")