Hoping for a minor miracle here...

I have a Clipper application running on a handheld device (Pocket PC).
I'm using PocketDOS as the OS on the handheld device. I'm trying to
port this application to a handheld running Windows CE 7.0. Although
I had some issues installing PocketDOS on the Windows CE device (was
unable to use the installer and had to install manually), I got it
installed and am able to launch and run the Clipper application on
this device.

The application runs fine until I try to create an index, then the
application fails when I try to use that index.

Example:

Program A uses the following statement:

use c:\SCANFILE.DBF index C:\SCANFILE.NDX alias SCANFILE

That works fine as long as I'm using the original index created on the
old Pocket PC handheld. Then I have a program that does:

if file( "SCANFILE.DBF" ) = .T.
if file( "SCANFILE.NDX" ) = .T.
erase ("SCANFILE.NDX")
endif
use SCANFILE.DBF
index on ITEM to SCANFILE.NDX
endif

That runs OK, but the next time I try to run program A, it fails on
the "use" statement with the error: "expression error ( in index key
)"

The database files and indexes were copied from the working device to
the new device. As stated, accessing the database files via the index
works OK initially, but when I try to recreate the index the program
then fails as described. If I re-copy the files, the program works
again until I try to recreate the index.

Any ideas out there?
--
Scott at Scott dash(-) Coffey dot net

Are you using xHarbour or Clipper?

--
Enrico Maria Giordano

http://www.emagsoftware.it
http://www.emagsoftware.it/emgmusic
http://www.emagsoftware.it/spectrum
http://www.emagsoftware.it/tbosg

On Mon, 19 Feb 2024 19:37:30 +0100, Enrico Maria Giordano
<e.m.giordano@emagsoftware.it> wrote:

>Are you using xHarbour or Clipper?

Clipper S87.
--
Scott at Scott dash(-) Coffey dot net

Il 20/02/2024 14:27, Scott Coffey ha scritto:

>> Are you using xHarbour or Clipper?
>
> Clipper S87.

It seems that the new index is not identical to the old one. Check the
index type (NDX/NTX/...) and the index key.

--
Enrico Maria Giordano

http://www.emagsoftware.it
http://www.emagsoftware.it/emgmusic
http://www.emagsoftware.it/spectrum
http://www.emagsoftware.it/tbosg

On Tuesday, February 20, 2024 at 8:03:17 AM UTC-6, Enrico Maria Giordano wrote:
> Il 20/02/2024 14:27, Scott Coffey ha scritto:
>
> >> Are you using xHarbour or Clipper?
> >
> > Clipper S87.
> It seems that the new index is not identical to the old one. Check the
> index type (NDX/NTX/...) and the index key.

S'87 manual Appendix F says the they "key" is damaged. I wonder if the executing program and indexing program are using the same version of compiler and libraries?

David A. Smith

OK, after doing some additional research, it appears there's a problem
with databases in general.

I have an application that writes records to a database. The writes
appear to be happening (I can open the database in Advantage Data
Architect and the records are there), but I can't read those records
in a subsequent program. The file being written to has no keys and no
associated indexes. So I can write to the file but can't read those
records from the file.

I have the handheld application working on a development PC. I can
take the file that was written on the handheld and copy it to the PC,
and the PC program reads the records with no problem.

The same handheld program that writes the records to the database
first validates that the item number being written is valid, so it
does a lookup via an index on another database. That function is
working. So it can access a database via index to validate a number,
but it can't read do straight reads from a database file.

Here is my compile script:

Clipper C:\Handheld\%1 -oc:\Handheld > errors.txt
IF NOT ERRORLEVEL 1 BLINKER FI C:\Handheld\%1 @c:\CLIPS87\BCL.LNK <
C:\Handheld\C.TXT
IF NOT ERRORLEVEL 1 DEL C:\Handheld\%1.OBJ

Here is my link script:

BLINKER INCREMENTAL OFF
BLINKER EXECUTABLE CLIPPER F45
# BLINKER CACHE XMS 1024, 25%
BLINKER CACHE EMS 1024, 25%
BLINKER OVERLAY FIXED
# BEGINAREA
# #LIB \CLIPS87\EXTEND
#LIB \CLIPS87\NANFOR
# ENDAREA
# FILE \CLIPS87\NDX
@\BLINKER\CLP\LNK\CL87MID.LNK

In summary, the application works on a handheld running Pocket PC OS.
It also works on a development box (A Windows 7 box running in XP
mode). But it's failing on a handheld running Windows CE 7.0. The
only different variable here is the PocketDOS implementation on the
Windows CE device. I've tried reaching out to PocketDOS, but their
stance is that it's a "DOS problem" and they can't help.

Do any of you oldsters out there know of any DOS tweaks that might
help here? Here is my autoexec.bat and config.sys:

autoexec.bat:

cls

rem -----
rem The following line sets the DOS PATH
rem -----
PATH A:\DOS

rem ----
rem Display drive settings (for information only)
rem Type: SETDRIVE /? for more information.
rem Note: SETDRIVE must be run from AUTOEXEC.BAT to enable saved
redirections
rem ----
SETDRIVE NOBANNER
echo.

C:
main.exe (<--- this is the Clipper executable)

*************************

config.sys:

rem ----
rem Load File System Redirector
rem ----
DEVICEHIGH=\DOS\PKTDOSFS.SYS

rem ----
rem Load Expanded Memory (LIM EMS 3.2) Driver
rem ----
DEVICEHIGH=\DOS\EMSMEM.SYS

*************************

Any ideas/suggestions are appreciated.
--
Scott at Scott dash(-) Coffey dot net

On Tuesday, February 20, 2024 at 10:56:55 AM UTC-6, Scott Coffey wrote:
> OK, after doing some additional research, it appears there's a problem
> with databases in general.
....
> Do any of you oldsters out there know of any DOS tweaks that might
> help here? Here is my autoexec.bat and config.sys:
>
> autoexec.bat:
>
> cls
>
> rem -----
> rem The following line sets the DOS PATH
> rem -----
> PATH A:\DOS

.... note the path.
> DEVICEHIGH=\DOS\PKTDOSFS.SYS

So you are instructing the OS to look in A:\DOS\DOS\... for that particular program. Why don't you display line by line (as makes sense) any error messages that you might be ignoring from instructions to 'DOS'?

> DEVICEHIGH=\DOS\EMSMEM.SYS

.... ditto

> Any ideas/suggestions are appreciated.

Before first line of executing code, add a diagnostic. Run DIR and wait, or run ADIR() and analyze. See where the code is looking for database and index. Alternatively, issue a SET DEFAULT to the druive and directory you want it to look in. Do this same thing for the code that (re)creates the index, or incorporate in the one program. S'87 had some limited error trapping, could put the code there.

David A. Smith