topic Re: Returning Status From Datatrieve (DTR) in Operating System - OpenVMS

Returning Status From Datatrieve (DTR)

Ramondo — Tue, 19 Dec 2006 20:40:16 GMT

Hi guys, only my second post here...

I don't know if anyone uses DTR anymore, but I'd like to know if it's possible to return a status to a command procedure to indicate when an error has occurred with a DTR command. Here's the situation:

Log of DTR within a command procedure to write a record to an RMS file that has "no duplicates" (simplified version)...

$
$ DTR
DATATRIEVE V7.2A
Digital Query and Report System
Type HELP for help

ready interface_domains.svoc_interface_tracking as trf write

store trf using
begin
run_number = "000001";
file_type = "NOTEIF";
extract_date = "20061220";
batch_status = "P";
data_flag = "N";
sched_seq_number = "000001";
file_seq_number = "01";
day_seq_number = "01";
end
You cannot store a duplicate value in an RMS key field that doesn't allow duplicates.

exit
$ l_stat = $status
$!
$ if .not. l_stat
$ endif
$!
$ exit

$status always has a value %X008D8CB9 on exit from DTR, no "on error goto" or checking of $status is going to pick up the fact that the record wasn't written.

Seeing as all the data in this case is character means I could use DCL to concatenate and $write/error=[err trap], but the DTR method seems more correct.

Redirecting the output to a separate log and searching for "You cannot store..." seems like too much trouble too.

Maybe it's not designed to be used this way.

Any thoughts?

Thanks,

Ramondo.

Re: Returning Status From Datatrieve (DTR)

John Gillings — Tue, 19 Dec 2006 22:07:40 GMT

Ramondo,

%X008D8CB9 is a DTR facility message, see:

$ WRITE SYS$OUTPUT F$MESSAGE(%X008D8CB9)
%DTR-S-NOMSG, Message number 008D8CB9

Since I don't have a DTRMSG file (DTR not installed here), I can't identify the actual message, but you may be able to. Try:

$ SET MESSAGE SYS$MESSAGE:DTRMSG

and repeat the above command.

The severity is -S- which means "Success", so whatever DTR has done, it's been considered successful.

By OpenVMS conventions, an image should return a longword status code in R0 when it exits. DCL makes that value available as $STATUS. It's entirely up to DTR to decide what to place in R0. My recollection is that DTR doesn't give you anything useful. However, it's been a long time, so I may be incorrect. There may also be switches or commands within DTR to return something to DCL which you can test.

Re: Returning Status From Datatrieve (DTR)

Ramondo — Tue, 19 Dec 2006 23:24:03 GMT

Thanks for the prompt reply.

DTR> exit
$ sh sym $status
$STATUS == "%X008D8CB9"
$ SET MESSAGE SYS$MESSAGE:DTRMSGs
$ write sys$output f$message("%X008D8CB9")
%DTR-S-EXIT, Exit from DATATRIEVE requested by operator.

It's the status of EXIT command at the end of my DTR session that it's returning.

If I remove the EXIT the last DTR command executed is the attempt to store the record - but same result. It seems there's an implied exit that returns the generic DTR Exit Status regardless of what's gone before.

I've had a look at DTR help and can't find anything relating to return of status codes...

Re: Returning Status From Datatrieve (DTR)

Keith Cayemberg — Wed, 20 Dec 2006 07:13:26 GMT

Hi Ramondo,

Actually the Callable DTR is intended to be used when you need that type of error handling control of Datatrieve functions. However there is a way to first grab the Datatrieve Status Value and then put it into your own DCL symbol. Please see the example below that has already worked for me.

$ mc dtr32 DEC DATATRIEVE V7.2
Digital Query and Report System
Type HELP for help
DTR> show mydomain
Element "MYDOMAIN" not found in dictionary.
DTR> FN$SET_SYMBOL("DTR_STATUS",FN$STATUS)
DTR> exit
$ set message sys$message:DTRMSGS.EXE
$ say f$message("%D''DTR_STATUS'") %DTR-E-ELTNOTDIC, Element "!AS" not found in dictionary.
$ show symbol DTR_STATUS
DTR_STATUS = "9273746"
$

Note that the DTR Status returned is a Decimal base 10 value.

Cheers!

Keith Cayemberg

Re: Returning Status From Datatrieve (DTR)

Ramondo — Thu, 21 Dec 2006 16:52:27 GMT

Cheers Keith.

I notice there's nothing in the online help about FN$STATUS, but there are lots of other functions listed.

Also, if you do nothing in a DTR session (as in no reads or writes), the status returned is zero. A value of 1 would be better, I think.

Anyhow, just what I needed.

Thanks again,

Ramondo.