Software Reference Manual - NetEx

Appendix B. BFX Internal Summary
The following paragraphs briefly summarize the internal structure of BFX as it relates to writing user modules.
Table 5 lists and describes the BFX default modules. All modules have 6-character names with the first
3 characters being BFX. Some references to the modules refer only to the last 3 characters of the name.
Immediately following Table 5 are three block diagrams showing the interaction of these modules in each of
the three BFX programs.
Module
BFXTIC
BFXTRC
BFXJSC
BFXPRM
BFXSCN
BFXSUB
BFXRCV
BFXSND
BFXCON
BFXMDT
Description
BFXTI entry point. Calls PRM to scan control parameters, calls the user- specified JMODULE
or the BFX default JMODULE to send the job to the remote host. Calls the SND or RCV module
to send or receive the file according to the user's parameters. If batched control statements
were provided, it continues the cycle until SYSIN is exhausted.
BFXTR entry point. Calls PRM to scan control parameters. Calls the SND or RCV module to
send or receive the file according to the user’s parameters. If batched control statements were
provided, it continues the cycle until SYSIN is exhausted.
BFXJS entry point. Scans JS control parameters and calls SCN to parse the parameters. Calls
RCV to receive the batch jobs from remote sources and submit them to the system internal
reader. Continues to call RCV until cancelled by the user.
Parameter scanner for control parameters to the BFXTI, BFXTR, and BFXJS programs. Parses
input and fills the TRansfer Option List (TROL) data structure with the user’s parameters
and/or BFX and installation-provided defaults.
Parser for control parameters. This breaks down the control parameters into tokens and returns
the tokens to the PRM or JSC calling routines.
BFX default job submission module. BFXSUB builds a new TRansfer Option List and calls
the BFXSND file send module to send it to the remote B FXJS program.
This module directs the process of receiving a file from a remote BFX program. If invoked by
TI, it will call CON to complete session negotiation from the OFFERing side. If invoked by
TR, it will call CON to connect to TI and negotiate parameters. When the connection is successfully
established, it will call the receiving block module to allow the data to be written to
the file. During transfer, it processes all generated informational and error messages, and detects
and handles error and EOF conditions.
This module directs the process of sending a file to a remote BFX program. If invoked by TI, it
will call CON to complete session negotiation from the OFFERing side. If invoked by TR, it
will call CON to connect to TI and negotiate parameters. When the connection is successfully
established, it will call the transmitting block module to obtain the data from the file. During
transfer, it processes all generated informational and error messages, and detects and handles
error and EOF conditions.
This module issues an SOFFER or SCONNECT request to allow another BFX program to connect
to it. When the connection completes, the module negotiates the file transfer parameters.
The module table is a non-executable module that contains a list of the currently available record,
block, and job modules. The table contains the entry address for each module as well as
flags that allow the correct high level language environment to be established before the mod-
MAN-REF-H211-05 Appendix B: BFX Internal Summary Page 77