Listing 9. Sample Data Write Function
struct input_event ev; /* the event */
/* we turn off all the LEDs to start */
ev.type = EV_LED;
ev.code = LED_CAPSL;
ev.value = 0;
retval = write(fd, &ev, sizeof(struct input_event));
ev.code = LED_NUML;
retval = write(fd, &ev, sizeof(struct input_event));
ev.code = LED_SCROLLL;
retval = write(fd, &ev, sizeof(struct input_event));
while (1)
{
ev.code = LED_CAPSL;
ev.value = 1;
write(fd, &ev, sizeof(struct input_event));
usleep(200000);
ev.value = 0;
write(fd, &ev, sizeof(struct input_event));
ev.code = LED_NUML;
ev.value = 1;
write(fd, &ev, sizeof(struct input_event));
usleep(200000);
ev.value = 0;
write(fd, &ev, sizeof(struct input_event));
}
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