> Despite the public documentation, Palm OS is a multi-tasking OS. I'm aware of that. I have myself posted here links to a program that demonstrates this:
http://flippinbits.com/twiki/bin/view/FAQ/HowDoICreateAThread That program definitely works under PalmOS 3.5 - maybe even under some of the earlier versions. Still, I'd rather avoid such tricks, if possible. > The following "undocumented" calls are identified in some of the > information that I gathered about YAHM: KALTaskCreate, > KALTaskDelay, KALTaskDelete, KALTaskGetCurrentID, KALTaskGetInfo, > KALTaskResume, KALTaskSuspend, KALTaskStart, KALTaskSwitching, > KALTaskWait, KALTaskWaitClr, KALTaskWake, KALTaskExit, > SysTaskCreate, SysTaskDelay, SysTaskDelayV40, SysTaskDelete. There is also a bunch of stuff related to semaphores that have meaning only in multi-tasking control: MemSemaphoreReserve, MemSemaphoreRelease, SysSemaphoreCreate, SysSemaphoreDelete, SysSemaphoreWait, SysSemaphoreSignal, SysTaskID, SysTaskUserInfoPtr, SysTaskSetTermProc, SysSemaphoreSet, SysRestoreStatus, SysResSemaphoreCreate, SysResSemaphoreDelete, SysResSemaphoreReserve, SysResSemaphoreRelease, SysTaskSwitching, SysTaskWait, SysTaskWake, SysTaskWaitClr, SysTaskSuspend, SysTaskResume; probably others. > There is very little documentation from Microsoft about how to > write a MSDOS TSR. Certainly not enough to write one. TSRs were > developed by the developer community, not by Microsoft. The > Microsoft attitude toward TSRs was primarily silence, with > occasional warnings and disclaimers. Not unlike what we're seeing > now with Palm. Dunno about Microsoft but I definitely learned how to write a TSR program from a DOS programmer's reference - although it might have been from one of the "clone" DOSes (e.g., PC-DOS). A better example is the hacks in PalmOS - Palm kept mostly silent about them and they were developed by the user community - although eventually Palm *does* mention them glancingly in the "official" documentation. > Not using undocumented facilities to detect viruses assumes that > all viruses follow the same rules. No, it doesn't. Countrary to popular belief, anti-virus programs and viruses don't play by the same rules. I usually don't need to do undocumented tricks in order to detect a virus that uses some. Occasionally, the opposite is also true - I might have to use undocumented tricks in order to handle a virus that does everything "by the book". > The idea that using only documented facilities will protect you > from changes in future OS versions is naive. Refraining from using undocumented features, of course, won't guarantee you a protection from quircks in futures versions of the OS. However, if you *do* rely on undocumented stuff, you're virtually guaranteed to have trouble with the new versions. > This is exactly what YAHM does. Palm is not going to tell you > how to do this without some legal leverage on how you use the > information. First, I don't think that I need it. Second, I don't believe that the author of YAHM got this information from Palm under NDA, did he? :-) Regards, Vesselin -- For information on using the Palm Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/
