Envoy Application Programming Manual
Table Of Contents
- What’s New in This Manual
- About This Manual
- 1 Application Programming With Envoy
- 7 ADM-2 Multipoint Supervisor Protocol
- 8 TINET Multipoint Supervisor Protocol
- 9 Burroughs Point-To-Point Protocol
- 10 Asynchronous Line Supervisor Protocol
- A ASCII Character Set
- B ASCII to EBCDIC Code Conversion
- C File-System Procedures
- D Statistics Messages
- E S-Series Changes to Envoy
- NonStop™ Himalaya S-Series Server Architecture
- G-Series Migration Considerations
- CBSENSEON and CFSENSEON Modifiers
- LEOTRESYN and NOLEOTRESYN Modifiers
- Treatment of Characters After the Termination Character
- Number of SYN Characters
- DTR Drop
- Reporting of Parity Error
- Half-Duplex Support for Asynchronous Lines
- Controller Replacement
- SYSGEN and COUP
- Unit Numbers
- FDX Line Changes
- No Support for Auto-Call Unit
- Glossary
- Index
ADM-2 Multipoint Supervisor Protocol
Envoy Application Programming Manual—427159-001
7-5
File-System Procedures
An operation that times out is retried the maximum of times specified by the retry count
before an error indication is returned to the application process.
File-System Procedures
The supervisor application process in an ADM-2 centralized multipoint network uses the
following Guardian 90 file-system procedures to interact with Envoy and the tributary
terminals:
AWAITIO
Waits for, or checks for, the completion of an outstanding nowait I/O operation.
CHANGELIST
Performs any of the following functions:
•
Enables or disables the polling or selection of a particular station
•
Alters the polling type (from continuous to noncontinuous or vice versa)
•
Resumes the polling of partially disabled (nonresponding) stations
If you call CHANGELIST while polling is in progress, Envoy waits until the polling
function is finished before performing the requested function.
CLOSE
Terminates access to a data communications line.
CONTROL
Performs the line control operation shown in Table 7-3
Table 7-2. Effect of the Timeout Value
Protocol State Effect of Timeout Value
During WRITE Determines the period of time following the selection of a terminal that
Envoy waits for an acknowledgment.
During READ Determines how long Envoy waits for an acknowledgment from a
polled terminal.