extern void persistfile( /* open persist file and lock it */ char *pfn ) { persistfd = open(pfn, O_WRONLY|O_CREAT|O_EXCL, 0644); if (persistfd >= 0) { persistfname = pfn; pflock(1); return; } /* file exists -- switch to i/o process */ persistfd = open(pfn, O_RDWR); if (persistfd < 0) { sprintf(errmsg, "cannot open persist file \"%s\"", pfn); error(SYSTEM, errmsg); } pflock(1); io_process(); /* never returns */ }
//SysTick Handler that will be called several times per second (see TICKS_PER_SECOND). This is an interrupt. void SysTick_Handler() { ticks++; io_process(); //Process button presses }