there is no memory protection in palmos so if process A allocates a chunk, nothing stops process B from reading (or writing) it. there IS semaphore, mutex, mailbox and event group api, but what Aaron said stands for these as well.
On 12/11/06, Lin George <[EMAIL PROTECTED]> wrote: > > Thanks Aaron! I want to confirm with you that, you mean each process can > only have one thread, right? > > Other issues are, > > 1. are there any ways to do inter-process communication, like what we did > on Linux/UNIX by using pipe/shared memory? > > 2. If the answer to 1 is yes, are there any inter-process synchronization > control approaches, like what we did on Linux/UNIX by using mutex/lock? > > > regards, > George > > ----- Original Message ---- > From: Aaron Ardiri <[EMAIL PROTECTED]> > To: Palm Developer Forum <[email protected]> > Sent: Monday, December 11, 2006 6:26:00 PM > Subject: Re: multi-threaded application in Palm OS 5.2 > > > On 12/11/06, Ben Combee <[EMAIL PROTECTED]> wrote: > > On 12/10/06, Lin George <[EMAIL PROTECTED]> wrote: > > > In my current understanding, Palm OS 5.2 only supports one application > > > (process) one thread -- means each process could only have one thread. > > > Is my understanding correct? > > > > You neither have multiple threads or multiple processes in standard Palm > OS > > programming. To switch applications, the current one ends, then the > system > > starts the new one. > > > > There is a limited background thread capability exposed through the > sound > > stream APIs. Also, applications can register for notifications where > their > > routines will be called while other programs are running. > > this is the official palmsource response. > > there is however, the ability to run true threads on palmos - the API is > system > use-only, however, it is really supposed to be used for small, simple > tasks. > how do you think your sms messages get delivered in the background? some > developers may have been able to tune into this - but, its not official. > > i know for sure; i use it to get more accurate timing for nilEvent > processing > when doing animations and games. i dont know what the limitations are > while > using the threads - for example; you may be restricted to a certain set of > API's and semaphore states in the callbacks. > > official answer: no > un-official answer: yes, but - if you dont know how - forget it. > > -- > // Aaron Ardiri > > -- > For information on using the PalmSource Developer Forums, or to > unsubscribe, please see http://www.palmos.com/dev/support/forums/ > > > > > ____________________________________________________________________________________ > Cheap talk? > Check out Yahoo! Messenger's low PC-to-Phone call rates. > http://voice.yahoo.com > > -- > For information on using the PalmSource Developer Forums, or to > unsubscribe, please see http://www.palmos.com/dev/support/forums/ > -- Best Regards, Dmitry Grinberg Software Engineer, http://PalmPowerups.com (847) 226 9295 AIM: DmitryGrinberg MSN: [EMAIL PROTECTED] ICQ: 165589894 Y! IM: dmitrygr2003 -- For information on using the PalmSource Developer Forums, or to unsubscribe, please see http://www.palmos.com/dev/support/forums/
