SNAX/XF and SNAX/APN Event Management Programming Manual

Glossary
SNAX/XF and SNAX/APN Event Management Programming Manual—426859-001
Glossary-9
header token
header token. In an SPI message, a token that provides information pertaining to the
message as a whole. Header tokens differ from other tokens in several ways: they exist
in the buffer at initialization and their values are usually set by SSINIT, they can occur
only once in a buffer, they are never enclosed in a list, they cannot be moved to another
buffer with SSMOVE, and programs cannot position to them or retrieve their values
using the NEXTCODE or NEXTTOKEN operation. Programs retrieve the values of
header tokens by passing appropriate token codes to SSGET and can change the values
of some header tokens by passing their token codes to SSPUT.
Examples of header tokens for commands are the command number, the object type, the
maximum-response token, the server-version token, the maximum-field-version token,
and the checksum token. Command and response messages contain a specified set of
header tokens; event messages, a different set with some overlap. See also SPI message
and data-portion token
.
header type. A token within the header token that indicates whether the message is an event
message or a command or response message.
host system. In an SNA network, a general-purpose processor that contains a subsystem
services control point (SSCP), PU type 5 logic, and one or more LUs representing
different applications or application subsystems. Typically an IBM mainframe running
VTAM, such as an IBM 3033. A Compaq NonStop™ system running SNAX/XF acts as
a host to attached SNA devices. See also mainframe
.
host-initiated passthrough. A passthrough mode in which the host application program
initiates a session. For host-initiated passthrough, the system manager must establish the
path between the gateway LU and the device when configuring the gateway LU; the
gateway LU must be defined with the PASSTHRU and ASSOCIATE attributes and,
optionally, the STATIC attribute.
I/O process. A system process that manages I/O hardware, such as in a Token-Ring or X.25
network configuration. Applications use the file system to send requests to I/O
processes.
INIT-SELF command. An SNA command issued by an initiating LU to request SSCP
assistance in establishing an LU-LU session with the named destination LU.
interactive command. In DSM, a command entered by a human operator rather than by a
program, usually through the Subsystem Control Facility (SCF) interface. See also
programmatic command
and Subsystem Control Facility (SCF).
interactive terminal interface (ITI). A 3270 application program interface that simplifies
communications between an application process and a 3270-type device by handling
SNA flows for interactive (line-at-a-time) communication.
interactive terminal interface (ITI) protocol. The protocol used to communicate with the
interactive terminal interface. The ITI protocol supports line-at-a-time communications
with certain SNA 3270-type display stations. Contrast with the CRT interface.
ITI. See interactive terminal interface (ITI)
.