OZAMIZ, Philippines — Linux, the operating system favored by many computer geeks over proprietary ones because it's free, is gaining ground among Internet cafés and business establishments in this southern Philippine city amid a crackdown against pirated computer software. The crackdown came in the wake of reports that software giant Microsoft is launching a low-priced Filipino version of Windows XP called Windows XP Starter Edition. It costs about $30 (1,680 pesos) as opposed to the Windows XP Home Edition that sells for $80 (4,480 pesos).