GDSX Manual

Service Routines
Extended General Device Support (GDSX) Manual–134303
8-46
^LISTEN
the buffer address is in local or extended memory by testing iocb.extaddr or
iocb.iocb^info.ext^io. For example:
IF iocb.extaddr THEN
BEGIN ! we have a extended memory buffer address
.
.
END
ELSE
BEGIN !we have a local memory buffer address
.
.
END;
•
For a message from $RECEIVE (message-flag is a nonzero value) the IOCB is as
follows:
The calling task should perform the requested operation and then call ^REPLY,
passing iocb.msgtag as the tag parameter.
•
For an I/O completion that is not an intertask message or a message from
$RECEIVE (i-o-message is a nonzero value) the IOCB is as follows:
iocb.syncid Sync ID of request
iocb.state 5 = I/O pending
iocb.optype 12 = ^READUPDATE operation
iocb.iocnt Length of request in bytes
iocb.cnt Maximum reply size
iocb.bufaddrx Buffer address where request resides. This will be a buffer
parameter to ^READUPDATE(0,..) or GDSX supplied buffer, if
the buffer parameter was omitted.
iocb.histag Nowait tag from call to ^READUPDATE(0...)
iocb.file 0
iocb.msgtag Message tag for request
iocb.rcbaddr Address of requester control block for opener making this
request.
iocb.state 5 = I/O pending
iocb.optype Type of operation completing
iocb.iocnt Count transferred from AWAITIO[X]
iocb.bufaddr[x] Buffer address from AWAITIO[X]