NetIPC 3000/XL Programmer's Reference Manual (5958-8600)

48 Chapter2
Cross-System NetIPC
Calls Affecting the Local Process
The intrinsics listed in Table 2-1 affect only local processes and
therefore have no adverse affects if used in a program communicating
with an unlike system (e.g., an HP 3000 program communicating with
an HP 1000 program). However, keep in mind that the calls (even those
of the same name) differ between system types. The following are some
local call differences of which you should be aware:
• Maximum number of sockets. The maximum number of socket
descriptors owned by an HP 3000 process at any given time is 64; on
the HP 1000 the maximum is 32; on HP 9000 systems, the maximum
is 60 (including file descriptors). On the PC, the maximum number of
socket descriptors is 21. This number includes both call socket and
virtual circuit socket descriptors.
•
IPCCONTROL parameters. The IPCCONTROL intrinsic supports
different sets of request codes on different system types. Refer to the
NetIPC documentation for a particular system (this manual only
documents the HP 3000) for a full description of the request codes
available on that system.
• Manipulation of descriptors. On the HP 3000, the IPCGIVE,
IPCGET, IPCNAME, and IPCNAMERASE calls can be used to
manipulate call socket descriptors. On the HP 9000, you can
manipulate call socket and destination descriptors with the
ipcname() and ipcnamerase() intrinsics. On the HP 1000, you
can only manipulate call socket descriptors with the IPCName and
IPCNamerase intrinsics. In addition, on the HP 1000, you can
manipulate call socket, vc socket, and path report descriptors with
the IPCGive and IPCGet intrinsics.
• Asynchronous I/O. The HP 3000 utilizes the MPE XL intrinsics
IOWAIT and IODONTWAIT to perform asynchronous I/O. On the
HP 9000 and HP 1000, The NetIPC intrinsics ipcselect() and
IPCSelect are used to perform asynchronous I/O. On the PC use
the NetIPC intrinsic IPCWait.
• Call sockets. On the PC, call sockets are called source sockets and
call socket descriptors are called source socket descriptors. Both sets
of terms are used in the same way.
NOTE There are many additional differences between local NetIPC calls for
the HP 3000 and those used for other HP systems. Because these
differences only affect the local node, they should not affect the
cross-system communication capabilities of your program. Refer to the
corresponding system’s NetIPC documentation for more information.