Use the DROP_ACTION field to specify the action that runs when the user drops a file on the control. The action must be capable of accepting a file argument.
Frequently, a control definition includes both a PUSH_ACTION and DROP_ACTION field. You can use the same action for the push and drop action.
For example, the following control, located in the Personal Applications subpanel, runs the X client xwud, which takes a file argument.
CONTROL Run_xwud
{
CONTAINER_NAME PerAppsSubpanel
CONTAINER_TYPE SUBPANEL
POSITION_HINTS 2
ICON XwudImage
PUSH_ACTION RunXwud
DROP_ACTION RunXwud
}