This is part of Win16 API which allow to create versions of program from one source code to run under OS/2 and Win16. Under OS/2 program can be running under Win-OS/2 if program is Windows NE executable, and with help on Windows Libraries for OS/2, if it is OS/2 NE executable. Here is a WLO to OS/2 API mapping draft
Retrieves the handle associated with a given pointer to a local memory object.
HLOCAL WINAPI LocalHandle( LPCVOID pMem );
pMem – Pointer to a memory block inside the local heap (returned by LocalLock).
Returns the handle of the object, or NULL if the pointer does not belong to the local heap. Call GetLastError.
This function is the inverse of LocalLock.
Useful when you only have a pointer and need the handle for other operations (e.g., LocalFlags, LocalSize).
HLOCAL h = LocalHandle(pData);
push p call LocalHandle