HMODULE

HMODULE is a Windows API type that represents a handle to a loaded module within a process. A module refers to a PE file that has been loaded into the process address space, typically a Dynamic Link Library (DLL) or an executable (EXE). The handle is obtained when a module is loaded via LoadLibrary, LoadLibraryEx, or retrieved with GetModuleHandle or GetModuleHandleEx, and it is used to perform various module-related operations.

Key uses of an HMODULE include retrieving exported symbols and module information. GetProcAddress takes an HMODULE and the name of an exported function or variable to return its address. GetModuleFileName can be used with an HMODULE to obtain the full path to the module file. GetModuleInformation and related APIs can report base address, size, and other attributes of the loaded module. HMODULE can serve as a base address for certain address calculations related to the module.

Lifetime and reference counting are important for HMODULE. Modules are kept loaded while their reference count is non-zero. LoadLibrary increments the count, and FreeLibrary decrements it. When the count reaches zero, the module is unloaded. After unloading, the HMODULE becomes invalid; it should not be used unless reobtained.

Notes: GetModuleHandle(NULL) returns a handle to the executable module of the calling process. HMODULE is an opaque, pointer-sized handle and is compatible across 32- and 64-bit applications. It is distinct from raw pointers to code and should be treated as a reference to a loaded module rather than as a direct memory address.