Hi Ingo, On Tuesday 13 February 2007 15:39, Ingo Molnar wrote: > > * Dmitry Torokhov <[EMAIL PROTECTED]> wrote: > > > > What are the semantics of async sys_async_wait and async sys_async ? > > > > Ooooohh. OpenVMS lives forever ;) Me likeee ;) > > hm, i dont know OpenVMS - but googled around a bit for 'VMS > asynchronous' and it gave me this: > > http://en.wikipedia.org/wiki/Asynchronous_system_trap > > is AST what you mean? From a quick read AST seems to be a signal > mechanism a bit like Unix signals, extended to kernel-space as well - > while syslets are a different 'safe execution engine' kind of thing > centered around the execution of system calls. >
That is only one of ways of notifying userspace of system call completion on OpenVMS. Pretty much every syscall there exists in 2 flavors - async and sync, for example $QIO and $QIOW or $ENQ/$ENQW (actually -W flavor is async call + $SYNCH to wait for completion). Once system service call is completed the OS would raise a so-called event flag and may also deliver an AST to the process. Application may either wait for an event flag/set of event flags (EFN) or rely on AST to get notification. -- Dmitry - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
