REM Create mutex:
SYS "CreateMutex", 0, 0, 0 TO hMutex%
REM Wait to acquire mutex:
REPEAT
SYS "WaitForSingleObject", hMutex%, 1 TO res%
UNTIL res% = 0
REM Release mutex:
SYS "ReleaseMutex", hMutex%
REM Free mutex:
SYS "CloseHandle", hMutex%