XmIsMotifWMRunning - A function that determines whether the window manager is running
Boolean XmIsMotifWMRunning (shell)
XmIsMotifWMRunning lets a user know whether the Motif Window Manager
is running on a screen that contains a specific widget hierarchy. This function
first sees whether the _MOTIF_WM_INFO property is present
on the root window of the shell's screen. If it is, its window field is used
to query for the presence of the specified window as a child of root.
Specifies the shell whose screen will be tested for mwm's presence.
Returns True if MWM is running.