"Opens" a plugin (allowing it to reserve resources at the start of a simulation). This command can only be called from the main script. Call it from the main script in the first simulation pass (usually with sim_handle_all argument). simOpenModule is not available in the C-API. Look at the default main script to get an idea about how to use simOpenModule, simHandleModule and simCloseModule.
C return value
(1) number result=simOpenModule(number sim_handle_all)
(2) number result=simOpenModule(string moduleName)
sim_handle_all: indicates that all plugins should be opened
moduleName: the name of the plugin that should be opened
Lua return values
result: -1 in case of an error, otherwise result is the number of plugins that executed the command.