Cascade DataHub Command Set


These commands are used internally by the Cascade DataHub and Cascade Connect.

Command Syntax

Commands have the following syntax:

(command arg1 arg1 ...)

The whole command must be surrounded by parentheses. The command name and its arguments are each separated by white space—single spaces, tabs, or carriage returns are allowed. For example, the following line of a custom configuration file tells the Cascade DataHub to create a new domain, named TestDomain.

(create_domain TestDomain)

Multiple-word strings must be in quotes. Numbers take their own values. Booleans are 0 for false and 1 for true.

Return Syntax

When the DataHub executes a command, it may return a success message or an error message. The returned message contains the original command, and some or all of the arguments for the command. These messages will be received by programs using the DataHub APIs for C++, Java, and .NET, but they will not be received by DataHub scripts. The two types of success messages are:

  • No arguments: (success command)
  • One or more arguments: (success command arg1)

Success messages are returned if the DataHub command acksuccess has been previously issued with a value of 1. A value of 0 means no success messages will be returned. Error messages are returned any time there is an error. There are four types of error messages:

  • No arguments: (error "-2: (command): error message")
  • One argument: (error "-2: (command arg1): error message")
  • Two arguments: (error "-2: (command arg1 arg2): error message")
  • More than two arguments: (error "-2: (command arg1 ...): error message")

Table of Contents

acksuccess - tells the DataHub to return success messages.
add - adds a value to a point.
alias - creates an alias point for an existing point.
alive - tells the Cascade DataHub that the client is running.
append - appends a string to the value of a point.
assembly - creates an assembly.
asyncsocket - sets up asynchronous communication on a socket.
attribute - creates an attribute.
auto_create_domains - automatically adds domains requested by clients.
auto_timestamp - adds timestamps to unstamped changes.
cread - creates and reads a point.
create - creates a new point.
create_domain - creates a new domain.
creport - creates a point and requests notification of changes.
cset - creates a point and assigns it a value.
cwrite - creates a point and writes information to it.
DDEAdvise - sets up the item for a DDEAdvise connection.
DDEConnect - makes a connection to a DDE service and topic.
DDEInit - initializes the DataHub to act as a DDE server.
DDEService - assigns a DDE service name.
DDEUnadvise - removes an item or point from a DDE connection.
debug - sets the debug level.
defaultprop - sets a default type for a property.
delete - deletes a point—use with caution.
deleted - checks if a point has been deleted.
div - does division on the value of a point.
domain - identifies the client domain name.
dump - writes the entire content of the DataHub to a file.
enable_dde_client - enables or disables DDE client capabilities.
enable_dde_server - enables or disables DDE server capabilities.
enable_mirror_master - enables or disables mirror master capabilities.
enable_mirror_slave - enables or disables mirror slave capabilities.
enable_opc_client - enables or disables OPC client capabilities.
enable_opc_server - enables or disables OPC server capabilities.
enable_scripting - enables or disables scripting capabilities
enable_tcp_server - enables or disables TCP server capabilities.
error - sends an error with an error string.
exit - shuts down the DataHub.
flush - flushes output to a terminal (Linux).
format - is an efficiency enhancement for Linux.
heartbeat - establishes a heartbeat message.
ignore - ignores a given point.
ignore_old_data - ignores changes with an old timestamp.
include - includes a file in with configuration files.
instance - creates an instance of a data organization model.
load_config_files - loads configuration files.
load_scripts - loads scripts.
lock - locks and unlocks points.
log_file - sets up a log file.
log_to_file - starts or stops logging to a file.
mirror_master - sets up a mirroring master.
mult - multiplies the value of a point.
OPCAttach - sets up an OPC connection.
OPCDetach - removes an OPC connection.
private_attribute - creates a private attribute.
property - creates a property for an assembly.
quality - assigns a quality to a point.
read - reads a complete point definition.
report - requests notification of changes to a data point.
report_domain - registers points and requests information on a whole domain.
report_errors - controls the reporting of errors.
request_initial_data - gets current data when client connection is made.
secure - adjusts the security level of a point.
set - sets the value of a point.
show_data - displays the Data Browser.
show_debug_messages - show or hide debugging messages in the Data Browser.
show_event_log - displays the Event Log.
show_icon - displays the system tray icon.
show_properties - displays the Properties window.
show_script_log - displays the Script Log.
subassembly - creates a subassembly.
success - sets up a success message.
tcp_service - sets a TCP service name or port number for incoming slave connections.
timeout - suspends data flow.
transmit_insignificant - permits tranmission of insignificant changes.
type - creates a type.
unreport - allows a client to stop receiving data value changes to a point.
version - returns the current version number.
write - writes information to a point.