Envoy Application Programming Manual

File-System Procedures
Envoy Application Programming Manual—427159-001
C-11
CONTROL
operation input
INT:value
is an integer value you use to specify the desired control operation. Table C-1
summarizes the CONTROL codes and operations. Refer to the protocol sections 4
through 11 for additional information on CONTROL operations.
parameter input
INT:value
is a subcode you use to further define the desired operation.
tag input
INT(32):value
applies to nowait I/O only. tag is a value you define to uniquely identify the
operation associated with this CONTROL call.
Condition Codes
Example
CALL CONTROL (fnum,19);
where fnum is the one-word integer variable specified in the OPEN call that opened the
particular communications line. In an asynchronous or byte-synchronous environment,
this call transmits a disconnect sequence (DLE EOT) and then disconnects the line by
clearing the data terminal ready (DTR) signal. The CONTROL codes used by the
various Envoy protocols are summarized in Table C-1.
< (CCL) Indicates that an error occurred (call FILEINFO).
= (CCE) Indicates that the CONTROL procedure was executed successfully.
Table C-1. CONTROL Operation Codes (page 1 of 3)
Operation Protocol Parameter Description
11 All 1 Sets DTR true and waits for DSR to
become true. See also CONTROL 17
13 1
BISYNC Point-to-
Point
.<0> 0: Sends EOT (end of transmission)
BISYNC
Multipoint
Supervisor
BISYNC
Multipoint
Tributary