Many of the EEM applet actions set some built-in variable to indicate their success status or store some result data. Unfortunately, these variables are not well documented...until now. Below is a list of actions and the variables that they instantiate (along with a brief description of what each variable contains).
Stores the sum of the previous addition operation
Contains the output from the
CLI command executed. It will be overwritten each time "action cli" is invoked
Stores the current value of a counter after the inc, dec, set, or nop operation has been performed
Stores the quotient and remainder respectively of the previous division operation
If the handle-error action is "ignore" then any error will be stored in the $_error variable. This error will be a string value. A healthy result is always "FH_EOK".