Dear Roemer
 
We have done this excersize. Major difference is that our application is
entirely based on Cobol.
 
Instead of rewriting calls to Image etc, we decided to encapsulate our
application in an "MPE emulation" package which runs on hp-ux an others,
taking care of converting VPLUS, Image, File Intrinsics etc calls - and it
works (currently we are using Informix). The components converted are:
Cobol -> MFCobol, TurboImage -> Informix, KSAM -> C-Isam, VPlus -> Curses,
Flat files -> software emulated Flat Files, other MPE intrinsics -> "mpe
shell"
 
We had a smooth migration to the hp-ux (and aix) with this path. I don't
think further technical details should be flushed to this list, but you
are welcome to contact me directly for more info.
 
Things to look out for: * Use of Image sorted chains. In our case it tends
to make a considerable overhead on the hp-ux version of our application.
* Use of Image record numbers (Next/Previous pointers) which is the
hardest part to emulate in a RDBMS. * Backward chained reads Luckily
Informix supports both forwards and backwards scroll cursors. * Whatch out
for the MF Cobol compiler on hp-ux. It is NOT as stable is the HP Cobol on
the 3k.
 
...Rewriting the application using "modern" tools? Show me a programmer
who wouldn't prefer that - but on the other hand, show me a manager who
happily wants to fund it...
 
Regards to everyone!
 
Flemming Rothmann ([log in to unmask])
-------------------------------
MIPS - The Aircraft Maintenance and Planning System.
CADO - The Flight Planning System.
Cimber Air Data A/S - The Aircraft Maintenance Software Company.
 
World Wide coverage - More info? Fax +45 74 43 28 22
 
On Thu, 9 Feb 1995, Rich Roemer wrote:
 
> Hi - I am interested in hearing from anybody who has experience porting a
> HP 3000 application to Unix.
>
[snip]