In an exemplary media implementation, one or more electronically-accessible media include electronically-executable instructions that utilize an application programming interface, the application programming interface facilitating creation of callback-type dynamic function tables; each callback-type dynamic function table including a begin address, an end address, and a callback function, each callback-type dynamic function table corresponding to a code heap that stores code for multiple functions in a runtime environment; wherein interaction between the runtime environment and an operating system is precipitated upon calling the callback function to acquire exception handling and/or unwind information. In another exemplary media implementation, one or more electronically-accessible media include at least part of an operating system that is configured to request from a runtime environment exception handling and/or unwinding information for functions that are managed by the runtime environment.