Calling External Native Functions

The Tachyon Operating System Native Interface (TNI) provides a way for 390 programs to call native functions. It provides a bridge between the 390 emulated memory and the external function’s memory, allowing parameters to be passed from the 390 program to the external function and then back again. On Windows, native functions may be written in C and packaged in a dynamic link library (DLL). The Tachyon Native Interface is not currently available for UNIX or Linux.

The TNI is invoked by calling the TOSNATIV subroutine, which may be linked to the calling program. The TOSNATIV subroutine can be found in &SYSDIR\csslib\tosnativ.obj where &SYSDIR is the directory into which the Tachyon Operating System was installed. The DSNMAP00.ini configuration file supplied with this version of the Tachyon Operating System provides the following definitions for SYS1.CSSLIB to allow a JCL invoked link edit to autocall the TOSNATIV subroutine:

The &SYSDIR\maclib\tosnativ.mac file contains a macro that defines the parameters required by the TOSNATIV subroutine. It also contains detailed information on the TOSNATIV subroutine parameters and other requirements.

The following files provide a complete example of using the TNI:

The provided example is somewhat useful in that it shows how a question can be asked of a user via a Windows dialog box and how the answer can be used to determine which of the subsequent job steps should be run.

Frames No Frames Previous Next Contents
Introduction Setup Programs Files Running Testing Compatibility Customization Messages Codes

© Copyright 1998-2004, Tachyon Software® LLC.
Last modified on August 31, 2004