/sys$common/syshlp/helplib.hlb MONITOR, MONITOR, Command Qualifier Descriptions, /INPUT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /INPUT[=(file-spec,...)]
       /NOINPUT (default)

    Controls whether performance data is played back from one or more
    input files or collected from the running system. If you specify
    more than one file, enclose the list in parentheses, and separate
    the file specifications with commas. Wildcard characters are
    allowed in the file specification.