[comp.os.vms] VMS <--> Ultrix network object communication

5401025@FSU.BITNET (05/26/88)

   I sent a previous inquiry about the subject about 10 days ago and it has not
shown up yet so i repeat.
   I have a network object (subsequently NO) on VMS 4.6 side which is tried to
be "opened" by a client program (subsequently CP) on Ultrix 2.0-1 over DECnet.
   NO OPENs SYS$NET and does several reads and then copies it to a local file.
   CP dnet_conn's NO and then writes to the socket.
   Well, at least that's what i want done. But somehow NO and CP are not
sinchronised, i feel, since NO gets an EOF on one of the reads (not the same
one every time) and CP exits fith no error at all (number of bytes written by a
WRITE is always equal to the number of bytes requested to be written).
   Also i am trying to use the select call to quiry i/o descriptors (the socket
in this case) for being ready for writing in order to attempt to sinchronise,
but am not having much luck mainly due to the fact that i don't know what i am
doing really.
   Has anyone had any experience with this? Please help.
---dubravko kakarigi, Supercomputer Computations Research Institute, FSU.

MACPHEDRAN@SASK.USASK.CA (05/28/88)

>Description: VMS <--> Ultrix network object communication
>Received: from JNET-DAEMON by SASK.USASK.CA; Fri, 27 May 88 08:09 CST
>Date: Wed, 25 May 88 10:13:00
>From: 5401025%FSU.BITNET@CORNELLC.CCS.CORNELL.EDU
>
>   I have a network object (subsequently NO) on VMS 4.6 side which is tried to
>be "opened" by a client program (subsequently CP) on Ultrix 2.0-1 over DECnet.
>   NO OPENs SYS$NET and does several reads and then copies it to a local file.
>   CP dnet_conn's NO and then writes to the socket.
>   Well, at least that's what i want done. But somehow NO and CP are not
>sinchronised, i feel, since NO gets an EOF on one of the reads (not the same
>one every time) and CP exits fith no error at all (number of bytes written by a
>WRITE is always equal to the number of bytes requested to be written).
>   Also i am trying to use the select call to quiry i/o descriptors (the socket
>in this case) for being ready for writing in order to attempt to sinchronise,
>but am not having much luck mainly due to the fact that i don't know what i am
>doing really.
>   Has anyone had any experience with this? Please help.
>---dubravko kakarigi, Supercomputer Computations Research Institute, FSU.

I have had similar problems with this sort of thing. A work around which
I used to combat it was to follow each read on the VMS side with a write
back to SYS$NET. I.e. the situation was:

CP: dnet_conn
ON: starts, opens SYS$NET
CP: write something to ON
ON: read from SYS$NET, write a dummy reply back to SYS$NET
CP: read from ON, send next write
ON: read from SYS$NET, write a dummy reply back to SYS$NET
CP: read from ON, send next write
etc.

Unfortunately, I have not gone back to fix this further. The problem
seems to be that the Ultrix program writes okay, but does not wait
for the remote end to read it, and things get confused. Manual
synchronisation is required. (Oh yes, in my case the ``ON'' was just a
DCL command file, so this may or may not solve your problem.)

Ian.
* Engineering Applications Programmer, University of Saskatchewan
* Instructional & Research Applications, Dept. Computing Services
* (MACPHEDR@SASK.BITnet)

5401025%FSU.BITNET%CORNELLC.CCS.CORNELL.EDU%KL.SRI.COM%lbl%sfsu1.hepnet@LBL.GOV (05/28/88)

Subject:  VMS <--> Ultrix network object communication
From:     5401025%FSU.BITNET@CORNELLC.CCS.CORNELL.EDU
Date:     Wed, 25-MAY-1988 10:13 To:       info-vax@kl.sri.com
Message-ID: <[gw.scri.fsu.edu].2651C8C0.0091358D.DUBRAVKO>
 
   I sent a previous inquiry about the subject about 10 days ago and it has not
shown up yet so i repeat.
   I have a network object (subsequently NO) on VMS 4.6 side which is tried to
be "opened" by a client program (subsequently CP) on Ultrix 2.0-1 over DECnet.
   NO OPENs SYS$NET and does several reads and then copies it to a local file.
   CP dnet_conn's NO and then writes to the socket.
   Well, at least that's what i want done. But somehow NO and CP are not
sinchronised, i feel, since NO gets an EOF on one of the reads (not the same
one every time) and CP exits fith no error at all (number of bytes written by a
WRITE is always equal to the number of bytes requested to be written).
   Also i am trying to use the select call to quiry i/o descriptors (the socket
in this case) for being ready for writing in order to attempt to sinchronise,
but am not having much luck mainly due to the fact that i don't know what i am
doing really.
   Has anyone had any experience with this? Please help.
---dubravko kakarigi, Supercomputer Computations Research Institute, FSU.