RE: Problem with QtmhCvtDb API -- MIDRANGE-L

To set the record straight.  This is NOT a bug in the QtmhCvtDb API.   The
solution you describe may make your symptom of the 0D25 causing the -4 for
invalid data go away by pushing it into a dummy variable.

Any program that reads a fixed number of bytes from standard input will be
a problematic CGI program.  The V3 and V4 HTTP servers use two different
systems for standard input and output.  The V3 server uses the AS/400
library file system.  The V4 server uses stream files.   Attempts to read
more than CONTENT_LENGTH will pick up these newlines that are part of the
stream file but not in your data since the newlines are beyond the
CONTENT_LENGTH.

Every HTTP server tells a CGI program the length of the data in standard
input using CONTENT_LENGTH.   On a UNIX web server, attempts to read more
than CONTENT_LENGTH will cause the CGI to loop forever waiting for input
since the server pipes standard input directly to the stream.  There is no
end of file on a stream.

Every CGI program should first check that the method is POST and then check
the CONTENT_LENGTH.  Only data with the POST method has data in standard
input.  The content length has how much data to read from standard input.
There is a sample C and RPG program on AS/400 technical studio and in the
web master guide that has correct CGI programs.   These program have worked
correctly since V3R2 without modification.

AS/400 Telnet Server/Client, WSG, LPD Server development
 Richard G. Hartmann       AS/400 TCP/IP & Server Development
  IBM T/L: 852-6731          IBM Mail: Richard Hartmann/Endicott/IBM
  Phone:   607-752-6731  Internet e-mail: rgh@us.ibm.com

------------------------------

Date: Wed, 20 Jan 1999 08:50:50 -0600
From: "Stone, Brad V (TC)" <bvstone@taylorcorp.com>
Subject: RE: Problem with QtmhCvtDb API

Ted Holt from Midrange Computing brought to my attention a Tech Talk item
concerning this, and it answered my question.  Apparently in V4R1 and up
there is a bug on this API when reading standard input.  The fix is to put
one more "dummy" variable at the end.

Bradley V. Stone
Taylor Corporation - OASIS Programmer/Analyst
bvstone@taylorcorp.com


> -----Original Message-----
> From:   rgh@us.ibm.com [SMTP:rgh@us.ibm.com]
> Sent:   Tuesday, January 19, 1999 8:04 PM
> To:     MIDRANGE-L@midrange.com
> Subject:     RE: Problem with QtmhCvtDb API
>
> It is important to remember CGI programs that read data from the standard
> input stream, only CONTENT_LENGTH bytes should be read from standard
> input.
> Attempts to read more than CONTENT_LENGTH bytes produces unpredictable
> results.   In this case, you have 0D25.
>
> In the technical studio on the AS/400 web page there are some RPG
snippets
> that will convert the character CONTENT_LENGTH to decimal to be used as
> the
> number of bytes to read parameter for QtmhRdStIn.
>
> When the last field is numeric and you read more bytes than
> CONTENT_LENGTH,
> you will get a -4 RC from QtmhCvtDb.   Your other application is working
> because the last field is character and the CRLF are just characters and
> not invalid for character data.    Although they would probably be
invalid
> if you used the data as a search parameter.
>
>  AS/400 Telnet Server/Client, WSG, LPD Server development
>  Richard G. Hartmann       AS/400 TCP/IP & Server Development
>   IBM T/L: 852-6731          IBM Mail: Richard Hartmann/Endicott/IBM
>   Phone:   607-752-6731  Internet e-mail: rgh@us.ibm.com
>
--------------------------------------------------------------------------
> -
> ------
>
> Date: Tue, 19 Jan 1999 10:53:31 -0600
> From: "Stone, Brad V (TC)" <bvstone@taylorcorp.com>
> Subject: RE: Problem with QtmhCvtDb API
>
> I just found another peculiarity.
>
> It's throwing a hex '0D25' at the end of my data (I'm guessing CRLF).
> Should it be doing this?  Could this be causing a problem or are these
the
> delimiter characters that it uses to signal the end of the data stream?
>
>
>
> Bradley V. Stone
> Taylor Corporation - OASIS Programmer/Analyst
> bvstone@taylorcorp.com
>
>
> > -----Original Message-----
> > From:   Stone, Brad V (TC) [SMTP:bvstone@Taylorcorp.com]
> > Sent:   Tuesday, January 19, 1999 8:28 AM
> > To:     'MIDRANGE-L@midrange.com'
> > Subject:     RE: Problem with QtmhCvtDb API
> >
> > Hi Stan.
> >
> > Yes.. trust me, this is the first thing I checked... and then checked
> > again... and again.. and again...
> >
> > I have since changed it for now, but it still doesn't work.  I am
having
> > the
> > user simply input one catalog number to run the report on.  It is now
> > skipping this field and still returning a -4.
> >
> > I know it's got to be something simple, because I have another
> application
> > that works just fine.
> >
> >
> > Bradley V. Stone
> > Taylor Corporation - OASIS Programmer/Analyst
> > bvstone@taylorcorp.com
> >
> >
> > > -----Original Message-----
> > > From: Staffan Lofberg [SMTP:staffan.lofberg@netorom.se]
> > > Sent: Tuesday, January 19, 1999 3:46 AM
> > > To:   MIDRANGE-L@midrange.com
> > > Subject:   Re: Problem with QtmhCvtDb API
> > >
> > > Brad
> > >
> > > Are you sure that you have the field CPTITM correctly spelled in the
> > > HTML-input?
> > >
> > > Staffan Lofberg
> > >
> > > "Stone, Brad V (TC)" wrote:
> > >
> > > > Hi Folks.
> > > >
> > > > Doing a little RPG/CGI programming and am having a problem.  I am
> > trying
> > > to
> > > > convert variables, but it is having problems on the last field and
> > > returning
> > > > a status code of -4 (means: An error occurred while converting the
> CGI
> > > input
> > > > string to the DDS defined data types. The data may or may not be
> > > usable).
> > > >
> > > > I can't find any other errors anywhere else.  The data structure
> gets
> > > filled
> > > > with the info needed except for the last one.  The DS looks like
> > this...
> > > >
> > > > CPDIV           3,0     Division Number
> > > > CPSUBDIV        3,0     Subdivision Number
> > > > CPFCAT          3,0     From Catalog
> > > > CPTCAT  3,0     To Catalog
> > > > CPFITM          14      From Item
> > > > CPTITM          14      To Item
> > > >
> > > > The user inputs a from and to catalog, and a from and to item
> number.
> > > These
> > > > are read in with the QtmhRdStin API.  The variable string looks
> good,
> > > and
> > > > everything is filled but the To Item number field on the Convert to
> > DB.
> > > >
> > > > Any ideas?  Return code of -4 doesn't tell me much.
> > > >
> > > > Bradley V. Stone
> > > > Taylor Corporation - OASIS Programmer/Analyst
> > > > bvstone@taylorcorp.com
> > > >
> > > > +---
> > >
> > > ------------------------------------------------------------------
> > > Netorom AB              Phone +46 40 6712272
> > > P.O. Box 9160           Fax   +46 40 940128
> > > S-200 39  Malm�         http://risc.netorom.se
> > > Sweden                  mailto:staffan.lofberg@netorom.se
> > >
>


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