datahub

datahub — starts the Cascade DataHub.

Synopsis

datahub [-aDhstUvVX] [-b size] [-d domain] [-f file] [-H home_path] [-l file] [-m port] [-M address] [-n domain] [-p port] [-q queue]

Arguments

-a

Transmit all point messages to all registered clients, even if the value does not change.

-b size

The maximum message buffer size.

-d domain

The domain name for this DataHub. This option can be used multiple times to get multiple domains on a single DataHub.

-D

Do not detach from the controlling tty. Normally the DataHub will detach itself and become immune to interrupts and termination on the controlling tty. If this option is used, then an & is necessary to run datahub in the background.

-f file

Load this configuration file.

-h

Print a help message showing a summary of all these arguments.

-H home_path

The full path to the directory that will contain the configuration and license files. This takes precedence over -U. If the directory cannot be found or created, the files will be stored in the installation directory.

-l file

Log messages to this file.

-m port

Acting as a TCP slave, attach to a TCP master on this port or service. The port is the matching port number of the master, usually 4600;

-M address

Acting as a TCP slave, attach to a TCP master on this host. The address is a machine name, such as developers.cogentrts.com or a machine address, such as 192.168.3.15.

-n domain

Acting as a TCP slave, mirror this domain from the TCP master. The named domain on the master will be mirrored to a domain of the same name in the slave.

-p port

Act as a TCP master and listen on this port/service.

-q queue

Specify an alternate queue name for this DataHub. Normally datahub chooses its own queue name to be unique on the network.

-s

Synchronized: The DataHub will ignore changes to a point if the point's current timestamp is more recent.

-t

Automatically generate a timestamp on unstamped points.

-U

The DataHub should NOT create a directory within the user's personal Application Data directory to store the configuration and license files, but rather in the application installation directory. This has a lower precedence than -H.

-v

Generate copious debugging information to the standard output. (Implies use of -D).

-V

Print the version number.

-X

Exit immediately (usually used with -V).

Returns

On success, nothing; on error, a message.

Description

The datahub command starts the Cascade DataHub. The DataHub does not use a configuration file since it is configured by its clients while running. Except where noted, the command line options apply to Cascade DataHub in Windows, Linux, or QNX, as well as Cascade Connect.

Dependencies

qserve, nserve

See Also

Using the Cascade DataHub, dhview, phdhview, xdhview

Example

[sh]$  datahub

Starts the DataHub in the domain default.

[sh]$  datahub -d control

Starts the DataHub in the domain control.