The full command-line option is /[NO]LIST[=file-spec].

    Controls whether a listing is created and optionally provides
    an output file specification for the listing file. Do not use
    wildcard characters in this file specification.

    If you enter the MACRO/ALPHA command interactively, the
    default qualifier is /NOLIST. The assembler sends output to
    the current output device rather than to a listing file. If you
    execute the MACRO/ALPHA command in a batch job, the default
    qualifier is /LIST.

    If you do not specify a file specification, the assembler creates
    a listing file using the same name as the source file. For
    example, if you use a source file named XXX.M64, the assembler
    creates a listing file named XXX.LIS.