Envoy Application Programming Manual

Table Of Contents
BISYNC Point-To-Point Protocol
Envoy Application Programming Manual427159-001
3-44
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Two “primitives” are used to perform READ and WRITE operations; they are read^text
and write^text, respectively. All message transfers have the following form:
DLE STX—text—ETX
Specifically, the program code in each process is given in the following programming
Example 3-18:
Example 3-17. Send Messages from the Local Station
Local Remote
CALL READ CALL READ
| |
| |
(READ completes) (READ completes)
error = 162 error = 162
CALL WRITE CALL READ
| ENQ --> |
| <-- ACK0 |
| message 1 --> (READ completes)
| error = 0
|
| CALL READ
(WRITE completes) <-- ACK1 |
error = 0 |
|
CALL WRITE |
| message 2 --> (READ completes)
| error = 0
|
| CALL READ
(WRITE completes) <-- ACK0 |
error = 0 |
|
CALL READ |
| EOT --> (READ completes)
| error = 163
|
(READ completes) CALL READ
error = 162 |
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