Hi,

yes, you will have access to the thread's local data, to the 
global static data, the heap and the stack. 

The <area> and <size> arguments to the isr can be used, for 
example, to have the same piece of code service different 
devices (prepare a descriptor structure fro each device, 
and attach a generic ISR to the interrupt, providing the
descriptor as the argument).

Regards,
- Thomas

> -----Original Message-----
> From: sathish kumar [mailto:community-noreply@qnx.com] 
> Sent: 11 February 2009 13:35
> To: ostech-core_os
> Subject: Interrupt handling in QNX
> 
> Hi All,
> 
> When an interrupt occurs in the hardware, the QNX interrupt 
> redirector loads the thread table entry and context of the 
> thread which the ISR is contained will be loaded. Does this 
> mean that the context of the entire process in which the 
> thread is a part is loaded or just the threads local data 
> section. Can i then access the global variables in the heap 
> area in ISR handler. Then in InterruptAttach( int intr,const 
> struct sigevent * (* handler)(void *, int),const void * 
> area,int size,unsigned flags) there is an area argument which 
> is not paged out . Could someone clarify why this area is 
> required if the entire context is loaded when the ISR occurs.
> 
> Thanks,
> 
> 
> 
> 
> _______________________________________________
> OSTech
> http://community.qnx.com/sf/go/post21954
> 
>