H06.05 Release Version Update Compendium

H06.05 Release Version Update Compendium—541761-001
2-1
2 Operating System
The H06.05 RVU contains these operating system changes:
•
Nonblocking Terminal I/O with OSS $ZTTnn
•
OSS Fileset
•
OSS Security APIs
•
POSIX Threads
Nonblocking Terminal I/O with OSS $ZTTnn
The HP NonStop Open System Services (OSS) environment includes a new terminal
helper server process, $ZTTnn (where nn is the processor number), in each processor.
The terminal helper server provides support for application use of the select() function
and the FILE_COMPLETE_ family of procedure calls on terminal device files such as
Telserv and OSSTTY. Each terminal helper server process automatically starts when
the processor it runs on is started. You cannot stop or start the new process
independent of processor shutdown or startup.
OSS Fileset
The OSS environment now includes its former process checkpointing and caching
features to improve fault-tolerance for OSS disk files. New fileset configuration options
enable separate control of checkpointing and caching and are implemented according
to whether the standard O_SYNC flag is used for an OSS file open. (The nonstandard
S_NONSTOP flag is now ignored.) The new default configuration settings provide the
recommended minimum level of fault tolerance, but it is possible to configure a fileset
for legacy fault-tolerant behavior.
You use the OSS Monitor Subsystem Control Facility (SCF) module command options,
rather than the storage subsystem SCF DISK command, to configure the
checkpointing and caching features. (The new fault-tolerant behavior requires disk
caching to remain enabled by the storage subsystem.) For more information, see the
Open System Services Management and Operations Guide.
Migration
Recode applications that use S_NONSTOP to use O_SYNC.
If your site prefers legacy fault-tolerant behavior to the defaults used by the updated
product modules, you must manually reconfigure that behavior after installation.
Fallback
If you fall back, filesets that you configured to use the new options before falling back
no longer use those options.