f



LAT to TCPIP using sys$qiow

We have a customer who, using LAT with sys$qiow to communicate
serial with other systems, wants to move to IP.  Examples would
be welcome, preferrably in PL/I but other languages would be OK
Tom
---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.655 / Virus Database: 420 - Release Date: 4/8/2004

0
tom284 (1839)
4/28/2004 2:50:46 PM
comp.os.vms 21904 articles. 1 followers. Post Follow

6 Replies
469 Views

Similar Articles

[PageSpeed] 12

"Tom Linden" <tom@kednos.com> writes in article <NDEMLKKEBOIFBMJLCECIEEHODCAA.tom@kednos.com> dated Wed, 28 Apr 2004 07:50:46 -0700:
>We have a customer who, using LAT with sys$qiow to communicate
>serial with other systems, wants to move to IP.  Examples would
>be welcome, preferrably in PL/I but other languages would be OK

See SYS$COMMON:[SYSHLP.EXAMPLES.TCPIP].

I'd recommend using the C socket functions instead of $qio[w].  You can even
use them from PL/I, although it might require a "wrapper" library.

--Keith Lewis              klewis {at} mitre.org
The above may not (yet) represent the opinions of my employer.
0
lewis12 (30)
4/28/2004 4:51:31 PM
Tom Linden wrote:

> We have a customer who, using LAT with sys$qiow to communicate
> serial with other systems, wants to move to IP.  Examples would
> be welcome, preferrably in PL/I but other languages would be OK
> Tom


I might have some samples of using FORTRAN & $QIO to communicate via TCP/IP, 
but I don't have any for PL/I.  Email me if you want them sent to you.


-- 
Chuck Chopp

ChuckChopp (at) rtfmcsi (dot) com http://www.rtfmcsi.com

RTFM Consulting Services Inc.     864 801 2795 voice & voicemail
103 Autumn Hill Road              864 801 2774 fax
Greer, SC  29651

Do not send me unsolicited commercial email.
0
ChuckChopp (87)
4/28/2004 5:26:29 PM
In article <c6onej$bk$1@newslocal.mitre.org>, lewis@spyder.mitre.org (Keith A. Lewis) writes:
> "Tom Linden" <tom@kednos.com> writes in article <NDEMLKKEBOIFBMJLCECIEEHODCAA.tom@kednos.com> dated Wed, 28 Apr 2004 07:50:46 -0700:
>>We have a customer who, using LAT with sys$qiow to communicate
>>serial with other systems, wants to move to IP.  Examples would
>>be welcome, preferrably in PL/I but other languages would be OK
> 
> See SYS$COMMON:[SYSHLP.EXAMPLES.TCPIP].
> 
> I'd recommend using the C socket functions instead of $qio[w].  You can even
> use them from PL/I, although it might require a "wrapper" library.

Regardless of programming interface, I believe such a change is going
to require quite a bit of change to the application, since LAT and
TCPIP have considerably disjoint characteristics.
0
Kilgallen (2738)
4/28/2004 8:41:33 PM
Larry Kilgallen wrote:

> In article <c6onej$bk$1@newslocal.mitre.org>, lewis@spyder.mitre.org (Keith A. Lewis) writes:
> 
>>"Tom Linden" <tom@kednos.com> writes in article <NDEMLKKEBOIFBMJLCECIEEHODCAA.tom@kednos.com> dated Wed, 28 Apr 2004 07:50:46 -0700:
>>
>>>We have a customer who, using LAT with sys$qiow to communicate
>>>serial with other systems, wants to move to IP.  Examples would
>>>be welcome, preferrably in PL/I but other languages would be OK
>>
>>See SYS$COMMON:[SYSHLP.EXAMPLES.TCPIP].
>>
>>I'd recommend using the C socket functions instead of $qio[w].  You can even
>>use them from PL/I, although it might require a "wrapper" library.
> 
> 
> Regardless of programming interface, I believe such a change is going
> to require quite a bit of change to the application, since LAT and
> TCPIP have considerably disjoint characteristics.


Actually, no, the overall change to the code is pretty minor as long as you 
continue using $QIO.  I did this kind LAT -> TCP/IP conversion back around 
1996 or so and it was in the realm of moderately trivial work.


-- 
Chuck Chopp

ChuckChopp (at) rtfmcsi (dot) com http://www.rtfmcsi.com

RTFM Consulting Services Inc.     864 801 2795 voice & voicemail
103 Autumn Hill Road              864 801 2774 fax
Greer, SC  29651

Do not send me unsolicited commercial email.
0
ChuckChopp (87)
4/28/2004 8:43:04 PM
Tom Linden wrote:
> We have a customer who, using LAT with sys$qiow to communicate
> serial with other systems, wants to move to IP.  Examples would
> be welcome, preferrably in PL/I but other languages would be OK

If the LTA device is set up external to the program, then you can do the 
same with a TNA device.  At that point the sys$qiow calls are the same.

The major difference is that if the LTA device becomes disconnected, an 
outstanding I/O will terminate with SS$_HANGUP.  The same I/O to a TNA 
device will hang unless your application has a time out.

If you are creating the LTA device in the application program, things 
are more complicated, and I have not been through that procedure for TCP/IP.

-John
wb8tyw@qsl.network
Personal Opinion Only

0
wb8tyw (629)
4/29/2004 2:01:58 AM
John E. Malmberg wrote:

> If you are creating the LTA device in the application program, things 
> are more complicated, and I have not been through that procedure for 
> TCP/IP.

The "UCX $QIO" interface is supported by *all* of the TCP/IP implementations 
that run on OpenVMS.  It is not necessary to create a TNA device in the same 
way that you would create an application LTA device.  Your application code 
can directly communicate with the IP stack and obtain an ephemeral socket 
for use with a TCP connection, and this simplifies things quite a bit since 
it eliminates the need for pre-defined terminals.


-- 
Chuck Chopp

ChuckChopp (at) rtfmcsi (dot) com http://www.rtfmcsi.com

RTFM Consulting Services Inc.     864 801 2795 voice & voicemail
103 Autumn Hill Road              864 801 2774 fax
Greer, SC  29651

Do not send me unsolicited commercial email.
0
ChuckChopp (87)
4/29/2004 2:43:52 AM
Reply: