[uClinux-dev] system_call: entry.S - Please reply

Greg Ungerer gerg at snapgear.com
Tue Mar 4 19:24:07 EST 2003

Hi Deepa,

Deepa Sivasankarane wrote:
>    In m68knommu/platform/5307/entry.S,  return values of 
> system_call/syscall_trace
> are in %d0. 
> movel %d3,%a0
>  jbsr %a0@
>  movel %d0,%sp@(LD0)  | save the return value 
> Where does one specify that the return value of all system calls is in %d0 ?

Exactly what are you asking?

It is explicitly coded in this entry.S file and in the libc library
system call stubs that %d0 contains the return value. There is no
single place it is specified. It is a convention that the kernel
and library must follow for it to work.


Greg Ungerer  --  Chief Software Wizard        EMAIL:  gerg at snapgear.com
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