Guardian Application Conversion Guide

Pool Space Address Adjustment
Considerations for Migrating Any Application
096047 Tandem Computers Incorporated D–5
Temporary File Names
Have 7 Digits
On D-series systems, the number of concurrent temporary files allowed per volume
has been increased. As a consequence, temporary file names now have 7 digits in their
name, after the pound sign (#).
On C-series systems, temporary file names had only 4 digits in their name
To ensure that your C-series application runs successfully on a D-series system,
modify your application if:
It expects the length of a temporary file name to be 4 digits.
It expects the (first) four digits of a temporary file name to be unique.
System-Message
Protocol for Process
Pairs Includes CPU
Down Message
On D-series systems, when a backup process takes over as the primary process
(following return from the CHECKMONITOR procedure) after the CPU of the
primary process fails, the backup process subsequently receives a CPU down (-2)
system message if it is reading system messages. Sending a CPU down (-2) system
message to the backup process ensures that the backup process sees all status
messages not seen by the primary process.
On C-series systems, the CPU down (-2) system message is not sent to a backup
process when it takes over as the primary process.
To ensure that your C-series application runs successfully on a D-series system, if it
accepts system messages but does not account for the CPU down (-2) message, you
might need to modify your application to take note of or react to the CPU down (-2)
system message.
Pool Space Address
Adjustment
Starting with the D20 release, the DEFINEPOOL and RESIZEPOOL procedures
sometimes adjust the starting address of a pool for address alignment. These
procedures also ensure that pool space overhead and adjustments for alignment do
not cause the pool to extend beyond the address that is the sum of the address
specified for the beginning of the pool plus the specified pool size.
If your application attempts to calculate precisely the amount of pool space that it
needs and does not allow for adjustment and alignment, it might not allocate adequate
pool space.
To ensure that your C-series application runs successfully on a D-series system, it
should not attempt to calculate precisely the amount of pool space that it needs (when
using the DEFINEPOOL and RESIZEPOOL procedures).