55 #  ifndef EV_USE_CLOCK_SYSCALL
56 #   define EV_USE_CLOCK_SYSCALL 1  macro
64 # elif !defined EV_USE_CLOCK_SYSCALL
65 #  define EV_USE_CLOCK_SYSCALL 0  macro
253 #ifndef EV_USE_CLOCK_SYSCALL
255 #  define EV_USE_CLOCK_SYSCALL EV_FEATURE_OS  macro
257 #  define EV_USE_CLOCK_SYSCALL 0  macro
279 # define EV_USE_REALTIME !EV_USE_CLOCK_SYSCALL
373 # undef EV_USE_CLOCK_SYSCALL
374 # define EV_USE_CLOCK_SYSCALL 0  macro
386 #if EV_USE_CLOCK_SYSCALL
393 #  undef EV_USE_CLOCK_SYSCALL
394 #  define EV_USE_CLOCK_SYSCALL 0  macro