Terminates send processing.
    Format
      MAIL$SEND_END  context ,in_item_list ,out_item_list
1 – Returns
    OpenVMS usage:cond_value
    type:         longword (unsigned)
    access:       write only
    mechanism:    by value
    Longword condition value. All utility routines return a condition
    value in R0. Condition values that can be returned by this
    routine are listed under Condition Values Returned.
2 – Arguments
 context
    OpenVMS usage:context
    type:         longword (unsigned)
    access:       modify
    mechanism:    by reference
    Send context information to be passed to send routines. The
    context argument is the address of a longword that contains send
    context information returned by MAIL$SEND_BEGIN.
    If send processing is successfully terminated, the value of the
    context argument is changed to 0.
 in_item_list
    OpenVMS usage:itmlst_3
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference
    Item list specifying options for the routine. This routine does
    not use the in_item_list argument.
 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. This routine does not use the out_item_list argument.
3 – Description
    The MAIL$SEND_END routine deallocates the send context as well as
    any dynamic memory allocated by previous send routine calls.
4 – Condition Values Returned
    SS$_NORMAL         Normal successful completion
    MAIL$_INVITMCOD    The specified item code is invalid.
    MAIL$_INVITMLEN    The specified item length is invalid.
    MAIL$_MISREQITEM   The required item is missing.
    SS$_ACCVIO         Access violation.
    Any condition value returned by LIB$FREE_VM.