TRANSFER Programming Manual

The TRANSFER Environment
An Overview of the TRANSFER Delivery System
1–6 40970 Tandem Computers Incorporated
Section 8, “Developing TRANSFER Applications,” contains guidelines for developing
a TRANSFER application and includes planning steps to help you determine whether
the TRANSFER delivery system is appropriate for your application environment.
The TRANSFER
Environment
A TRANSFER application can run under the PATHWAY transaction processing
system, taking advantage of the requester-server model on which all PATHWAY
applications are based. In the PATHWAY environment, the application programs are
requesters written in the SCREEN COBOL programming language and are used to
control terminal input/output. In general, requesters for a TRANSFER application fit
into the operating environment in the same way as requesters for other PATHWAY
applications fit into the operating environment.
Outside the PATHWAY environment, application programs can be modules coded in
COBOL, FORTRAN, the Transaction Application Language (TAL), Pascal, or C.
Note When you select a programming language (or languages) for your application programs, note that all
TRANSFER operations require data definitions in your programs. Tandem provides data definition files
for programs written in SCREEN COBOL, COBOL, FORTRAN, and TAL. Tandem does not supply
definition files for programs written in Pascal or C; for these programs, you must write your own definitions
using the specifications that appear in the TRANSFER Reference Manual.
The TRANSFER delivery system uses the Transaction Monitoring Facility (TMF) to
protect files that store or receive packages during the delivery process. If a failure
occurs while a package is in transit, the delivery operation is aborted and started over
again. In the event of a system failure, TMF allows you to recover the files.
Types of
Application Processes
A TRANSFER application consists of a set of processes that communicate with each
other and work together to perform a common task. These processes might run on
different CPUs or even at different nodes in a network. The entire application includes
TRANSFER processes and user processes, which are defined as follows:
TRANSFER processes are furnished either as part of the TRANSFER delivery
system or are provided by PATHWAY and operate with the TRANSFER delivery
system.
User processes are processes for which you, the application programmer, write the
code.