HP-UX 11i June 2002 Release Notes

Internet and Networking Services
STREAMS/UX
Chapter 12
221
STREAMS/UX
new at 11i
original release
Several enhancements have been made to STREAMS/UX, including support for the
select() system call, an I/O forwarding mechanism, and Function Registering:
• The select() system call for STREAMS/UX devices examines the files or devices
associated with the file descriptors specified by the bitmasks, readfds, writefds,
and exceptfds.
The select() system call can detect out-of-band (OOB) data on TCP by calling an
internal command, hpstreams_select_int2(), which contains a check in the
exception case for T_EXDATA_IND messages.
• STREAMS/UX contains an I/O forwarding mechanism that preserves the order of
messages and forwards those messages. This mechanism is particularly useful on
multi-node systems where driver events can only be executed on the node where the
NIC resides.
• Function Registering enables modules and drivers to work in a mixed mode system.
It provides the modules and drivers within the kernel a mechanism for correctly
translating data that is being sent to and from the application when STREAMS/UX
determines that the application has been compiled for 32-bit execution, but is
operating on a 64-bit architecture.
Function registering defines dynamic data structures and stream head flags, which
will indicate when and if a dynamically specified function is to be executed. These
data structures and flags can be set dynamically or on the fly.
NOTE UP Emulation will no longer be supported on HP-UX in a future release. Therefore,
drivers and modules that are configured as UP emulation drivers and modules should be
made MP scalable in preparation.
For more information about these changes, see the STREAMS/UX for the HP 9000
Reference Manual.