MAIL$_MESSAGE_BEFORE
    When you specify MAIL$_MESSAGE_BEFORE, MAIL$MESSAGE_SELECT
    selects a message received before a specified date and time. The
    buffer address field of the item descriptor points to a buffer
    that contains a character string 0 to 255 characters long in
    absolute time.
    Specify a value from 0 to 255 in the buffer length field of the
    item descriptor.
 MAIL$_MESSAGE_CC_SUBSTRING
    MAIL$_MESSAGE_CC_SUBSTRING specifies a character string that must
    match a substring contained in the CC: field of the specified
    message. If the strings match, the message is selected. The
    buffer address field of the item descriptor points to a buffer
    that receives a character string 0 to 998 characters long.
    Specify a value from 0 to 998 in the buffer length field of the
    item descriptor.
 MAIL$_MESSAGE_FLAGS
    MAIL$_MESSAGE_FLAGS specifies bit masks that must be initialized
    to 1.
 MAIL$_MESSAGE_FLAGS_MBZ
    MAIL$_MESSAGE_FLAGS_MBZ specifies Mail system flags that must be
    set to 0.
 MAIL$_MESSAGE_FOLDER
    MAIL$_MESSAGE_FOLDER specifies the name of the folder that
    contains messages to be selected.
    The buffer address field of the item descriptor points to a
    buffer that contains a character string 0 to 255 characters long.
    Specify a value from 0 to 255 in the buffer length field of the
    item descriptor.
    This item code is required.
 MAIL$_MESSAGE_FROM_SUBSTRING
    MAIL$_MESSAGE_FROM_SUBSTRING specifies a user-specified character
    string that must match the substring contained in the From: field
    of a specified message. If the strings match, the message is
    selected.
    The buffer address field of the item descriptor points to a
    buffer that receives a character string 0 to 998 characters long.
    Specify a value from 0 to 998 in the buffer length field of the
    item descriptor.
 MAIL$_MESSAGE_SINCE
    When you specify MAIL$_MESSAGE_SINCE, the Mail utility selects a
    message received on or after a specified date and time.
    The buffer address field of the item descriptor points to a
    buffer that contains a character string 0 to 255 characters long
    in absolute time.
    Specify a value from 0 to 255 in the buffer length field of the
    item descriptor.
 MAIL$_MESSAGE_TO_SUBSTRING
    MAIL$_MESSAGE_TO_SUBSTRING specifies a user-specified character
    string that must match a substring contained in the To: field
    of a specified message. If the strings match, the message is
    selected.
    The buffer address field of the item descriptor points to a
    buffer that contains a character string 0 to 998 characters long.
    Specify a value from 0 to 998 in the buffer length field of the
    item descriptor.
 MAIL$_MESSAGE_SUBJ_SUBSTRING
    MAIL$_MESSAGE_SUBJ_SUBSTRING specifies a user-specified character
    string that must match a substring contained in the Subject:
    field of a specified message. If the strings match, the message
    is selected.
    The buffer address field of the item descriptor points to a
    buffer that contains a character string 0 to 998 characters long.
    Specify a value from 0 to 998 in the buffer length field of the
    item descriptor.
 out_item_list
    OpenVMS usage:itmlst_3
    type:         longword
    access:       write only
    mechanism:    by reference
    Item list specifying the information you want the routine to
    return. The out_item_list argument is the address of a list of
    item descriptors, each of which describes an item of information.
    The list of item descriptors is terminated by longword value of
    0.