as the network will lose a USM without notifying the sender when
          an error is detected.
            status.i2.v = NTSEND( [lognod.i2.r],[tsknam.i4.r],msgadr.i2a.r,
                                   msglen.i2.r )
            status.i2.v = NET_SEND( [lognod.i2.r],[tsknam.i4.r],
                                    msgadr.i2a.r,msglen.i2.r )
         lognod   word giving the destination logical trunk and node
                  If defaulted, the local default logical node
                  is assumed.
         tsknam   longword giving the network task name of the
                  destination task (in Radix-50 form).  If defaulted,
                  the network task name of ACNET is used.
         msgadr   address of a buffer of words to be sent as the user
                  data portion of the message.
         msglen   word giving the number of words in the buffer to
                  be sent.
         status   returns ACNET Global Status (sign-extended to 32-bits):
                      =0 for complete success
                      >0 for conditional success and pending
                      <0 for error condition
         The error codes returned are:
            -02 = Local system out of space: no free buffers
            -21 = not connected to network
            -22 = insufficient number of arguments
            -23 = invalid message: too long or length of 0.
            -30 = no such logical node
            -43 = system service error: no network process.
            -44 = nontranslatable error: XSC block does not exist
            -45 = internal network error
            -48 = network error #3:
                - buffer vector in use
                - already waiting for transmission to complete.