/LOG_FILE[=filespec]
       /NOLOG_FILE

    Names the log file. The asterisk (*)  and the percent sign (%)
    wildcard characters are not allowed in the file specification.

    When you use the /LOG_FILE qualifier, the system writes the batch
    job's output to the file you specify. If you use the /NOLOG_FILE
    qualifier, no log file is created. By default, a log file is
    created, is written to the directory defined by the logical name
    SYS$LOGIN in the UAF, and is given the batch job's name as its
    file name with a file type of .LOG.

    You can use the /LOG_FILE qualifier to write the log file to
    a different device. Logical names in the file specification
    are translated in the context of the process that submits the
    job. The process executing the batch job must have access to the
    device on which the log file will reside.

    If you omit the /LOG_FILE qualifier and specify the /NAME
    qualifier, the log file is written to a file having the same
    file name as that specified by the /NAME qualifier with the file
    type .LOG. When you omit the /LOG_FILE qualifier, the job-name
    value used with the /NAME qualifier must be a valid file name.