Beside normal QM variables, you also can also use other media to store data.
When QM starts, it receives a copy of system environment variables. You also can create and use your own environment variables. Your environment variables exist until QM exits (differently than normal global variables, that are destroyed when loading other file or reloading current file). Environment variables are strings.
To get/set/delete environment variables, use functions GetEnvVar and SetEnvVar.
QM file commands, dll, menus, toolbars, etc automatically expand environment variables. See also: str.expandpath.
Environment variables usually are inherited from parent process, however not always.
To associate some values with a window, you can use window properties. A window property is some numeric value (it can be int, pointer or lpstr), which has some name and can be set/retrieved/deleted using functions SetProp, GetProp and RemoveProp. Examples:
RECT* r r._new SetProp(hwnd "ra" r) ... r=+GetProp(hwnd "ra") ... RemoveProp(hwnd "ra") r._delete
Call RemoveProp when destroying the window, for example on WM_NCDESTROY message. Read more about these functions in MSDN library.
You can use functions rget and rset to save variables in the registry.
You can use __ProcessMemory class to allocate, write and read memory in context of other process.
Some dlls export variables. You can declare such variable as dll function, but you cannot use it directly as variable. Instead, use it indirectly through reference or pointer variable. Example:
dll adll #_variable int+& _var = &_variable now _var can be used as dll variable _variable