GDSX Manual

Intertask Communication Example
Extended General Device Support (GDSX) Manual–134303
E-6
USAMPLE3
192. Call ^ReadupdateX(Dolr^RCV,RCV^Buf,132);
193. End
194. Else
195. -- write the data message to our device
196. Call ^WriteX(Term^File^Num, Buffptr, RCV^Iocb.Iocnt);
197. End;
198.
199. -----
200. E^ITC -> ! an intertask message
201. -----
202. Begin
203. -- get the address of the IOCB
204. @ITC^Iocb := ^Listen (0,0,1);
205. @BuffPtr := ITC^Iocb.BufaddrX;
206. -- write the message to our device
207. Term^Buf ':=' Buffptr for ITC^IOCB.Iocnt Bytes;
208. Call ^WriteX(Term^File^Num, Term^Buf, ITC^Iocb.Iocnt);
209. -- tell our partner task that we are finished
210. Call Notify^IO^CompletionX(ITC^Iocb);
211. -- do a ^READUPDATE for the next ITC message
212. Call ^ReadupdateX(Rcv^ITC^Fnum);
213. End;
214.
215. -----
216. E^IOC -> ! from our device (terminal)
217. -----
218. Begin
219. -- get the address of the IOCB
220. @Dev^Iocb := ^LISTEN (0, All^Files, 0);
221. @BuffPtr := Dev^Iocb.BufaddrX;
222.
223. If BuffPtr = ["ITC:"] Then Begin
224. -- our ITC message has been processed; our partner has
225. -- called NOTIFY^IO^COMPLETIONX so we reply to
226. -- $RECEIVE and do another ^READUPDATE
227.
228. -- because the value of LastrcvIOCB is cleared in
229. -- SEND^ITC^MSGX, we have to provide the tag
230. -- as the fourth parameter to do a real reply
231. -- and to deallocate the IOCB
232. Call ^REPLYX(,,,Dev^IOCB.MsgTAG);
233. Call ^READUPDATEX(DOLR^RCV,RCV^BUF,132);
234. End
235. Else Begin
236. -- check for our partner task only the first time
237. If W^Fcbaddr = -1D Then Begin
238. -- find our partner task
239. If My^Dcb.Name = ["$GDSX.#TASK1"] Then
240. Term^Buf ':=' "$GDSX.#TASK2"
241. Else
242. Term^Buf ':=' "$GDSX.#TASK1";
244. Term^Buf^Len := 12;
245. W^Fcbaddr := 0D;
246. W^Dcbaddr := 0D;
247. If Error := Get^ITC^FCB(Term^Buf:Term^Buf^Len,
248. W^Fcbaddr,
249. W^Dcbaddr) Then
250. W^Fcbaddr := -1D;
251. End;
252.
253. If W^Fcbaddr > 0D Then Begin
254. -- the message that we wrote on our device completed,
255. -- so write the message to our partner task
256. ITC^Buf ':=' "ITC: " & Buffptr For Dev^IOCB.IOCNT Bytes;
257. @Fcb^Ptr := W^Fcbaddr;
258. Call Send^ITC^MsgX (Fcb^Ptr,
259. ITC^Buf,
260. (Dev^IOCB.IOCNT + 6),
261. 0,
262. -1D,
263. 1); -- write operation
264. End;
265. End;