| Feature | EXE | DLL | |---------|-----|-----| | | WinMain or main | DllMain | | Execution | Creates its own process | Loaded into another process's address space | | Startup | OS loader starts a new thread | Called via LoadLibrary | | Exit Behavior | Terminates process; releases all resources | Unloaded; may leave resources if not freed | | Relocations | Optional (preferred base often fixed) | Required (can be loaded anywhere) | | Exports | Rarely exports functions | Designed to export functions |
A developer may have written a utility as a standalone console application (EXE) only to realize later that its logic is needed inside a larger GUI application. Instead of spawning a new process (calling the EXE from the main app), which is resource-intensive and complicates inter-process communication (IPC), it is far more efficient to convert the logic into a DLL. This allows the main application to call functions directly, sharing memory space and running faster. exe to dll
return TRUE;