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ND 10609 COSMOS Programmers Library¶

INTRODUCTION¶

COSMOS Programmers Library is a set of routines for those who need to write their own data communication software.

FEATURES¶

Use of TLIB from PLANC
Use of TLIB from FORTRAN
Use of XMSG from PLANC
Use of XMSG from FORTRAN

PRODUCT DESCRIPTION¶

XMSG:

XMSG is a system made for communication between tasks. The two communicating tasks may reside in the same system or in different systems. By task we mean: driver, direct task or RT (foreground or background) program. XMSG allows tasks to send messages to each other, including the handling of memory allocation, queuing, and task synchronization. A message may be securely sent, and it will be returned to the sender if it does not reach the receiver.

XMSG includes software on OSI level 2 and 3. It also includes most of level 4, except the very upper part. On level 2 the protocol is our version of LAPB.

TLIB:

TLIB stands for Transport LIBrary. It is a tool for data transfer between RT programs (including background programs). These programs may or may not reside in different systems.

The services offered by TLIB are similar to those offered by the OSI Transport Service Specification. Many of the TLIB concepts are taken from the OSI reference model. The current implementation of TLIB consists of a set of routines interfacing with XMSG.

Advantages to XMSG:¶

High performance
Minimal software size in the transport medium

Advantages to TLIB:¶

An XMSG-independent interface, similar to the OSI Transport Service
The provision of a flow-control mechanism, which means that the sending rate is adapted to the receiving rate.

REQUIREMENTS¶

ND-100, ND-500, or ND-SATELLITE computer systems
SINTRAN III version H or later
SINTRAN must be generated for XMSG

For intersystem communication also required:

HDLC or Megalink interface
SINTRAN generated for HDLC

DOCUMENTATION¶

COSMOS Programmer Guide .................ND-60.164