Use to define the environment variables for the Apama correlator and IAF instances. The defined variables are set when you start the instances. You can define the environment variables using the web interface and the command line interface. You can define the environment variables only when you update the configuration of an instance. The environment variables must be defined in key-value pairs syntax as a properties file. Use the sagcc update configuration data command to define the environment variables. If an environment variable is already defined and if you define that environment variable again, the old value is replaced by the new value.

You can use an existing environment variable in the definition of a new environment variable using the syntax ${env:EnvironmentVariableName}. The same syntax can also be used to update the value of an existing environment variable, for example:

Where the value of the MY_BIN environment variable during runtime is C:\project1\bin. The value of the PATH environment variable after the update is C:\project1\bin; C:\Program Files. Environment variables are evaluated and defined when an instance is started. Any existing environment variable used with the syntax ${env:EnvironmentVariableName} is replaced with its current value known at the time of evaluation. If an environment variable is not defined and is used in another environment variable, the undefined variable is replaced by an empty string. For example:

In the above example, the value of the MY_BIN environment variable is /bin, because ${env:MY_HOME} is replaced by an empty string. The order of defining an environment variable is very important. The environment variable used in the definition of another environment variable must be defined before it is used. For example, if you want to use MY_HOME in the definition of MY_BIN, ensure that you have defined MY_HOME before using it MY_BIN.

You can also use special substitution variables when defining an environment variable. The special substitution variables must be used in the syntax ${VARIABLE_NAME}. At present, only the following special substitution variables are supported:

Example for using special substitution variables:

You can use the special substitution variable $ to escape any defined or undefined environment variables, and special substitution variables. That is, if you want to use ${ENV_VAR} as a value and do not want it to be expanded, you should use $ as ${$} so that ENV_VAR is not expanded and the value will be ${ENV_VAR}. For example:

The values of ENV1, ENV2, ENV3 and ENV4 are:

Example format of a properties file: