OSI/TS Configuration and Management Manual

NonStop Kernel File-System Interface
OSI/TS Configuration and Management Manual—424831-001
7-8
Preparing to Establish a Connection
The OSI/TS subsystem bypasses the file-system PFS (process file segment)
buffering and initiates I/O operations directly from its buffer. This is transparent
to your application program.
The following subsections describe the procedure calls you use to set up and
manage a transport connection. Figure 7-1
and Figure 7-2 illustrate that the
sequence of calls differs depending on whether the OSI/TS subsystem or the
application manages the response to a connection request.
Note that applications at both ends can perform setup concurrently (as shown in
the figures), but that they do not have to do so. Note also that the connection
establishment/data transfer/connection release sequence shown in each figure can
be repeated many times before applications at both ends close the
communications path.
OPEN procedure Establishes a communications path between the
application and the OSI/TS subsystem.
SETPARAM fetches and sets subdevice characteristics (optional).
SETMODE and
SETMODENOWAIT
Initialize subdevice parameters to their configured values
and enables out-of-sequence completions when nowait
I/O is specified.