Library /sys$common/syshlp/mailhelp.hlb ANSWER, Qualifiers, /SIGNATURE_FILE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /SIGNATURE_FILE[=file-name]
       /NOSIGNATURE_FILE

    Specifies a file to be appended to the end of a mail message.
    The signature file contains text and has a default file type of
    .SIG. An example of a signature file is a text file formatted
    as business card, containing the user's company name, address,
    telephone, and Internet address.

    Specify the /SIGNATURE_FILE qualifier when you want to override
    the default established by the SET SIGNATURE_FILE command (if you
    want to send a signature file that is different from that default
    specification). If there is no default setting, specify the
    /SIGNATURE_FILE qualifier to interactively include a signature
    file with a particular mail message.

    To determine if the SET SIGNATURE_FILE command is in effect, use
    the SHOW SIGNATURE_FILE or SHOW ALL command.

    When you use the /SIGNATURE_FILE qualifier, note the following:

    o  When you create a mail message that includes a signature
       file, that message requires more temporary disk space than
       a conventional message because temporary files are created
       during the operation. After the message is sent, those
       temporary files are deleted.

    o  If you do not specify a directory, the Mail utility looks for
       the signature file in your mail directory.

    o  If you do not specify a file, the Mail utility uses the file
       specification in your user profile. If there is no default
       signature file in the profile, Mail will send the message
       without one.

    o  If a specified signature file does not exist, the system
       displays an error message.

    Specify the /NOSIGNATURE_FILE qualifier when you do not want
    to include a signature file with a particular mail message.
    Specifying this qualifier overrides the current setting,
    including any specifications in your user profile.