Re: x86_64 system call entry points II

[Andi Kleen <ak@suse.de>]

Martin Bisson <bissonm@discreet.com> writes:
> 
> - int $0x80/64 bits: All system calls return -1 (EINTR).  Is there
> something wrong in the way I call it:
> pid_t getpid64()
> {
>     pid_t resultvar;
> 
>     asm volatile (
>     "int $0x80\n\t"
>     : "=a" (resultvar)     : "0" (__NR_getpid)
>     : "memory");
> 
>     return resultvar;
> }

I tested it now. Since it ends up as a 32bit syscall you're not 
actually calling 64bit getpid() - but 32bit mkdir(). That is because 32bit and 64bit
have different syscall numbers. For me it returns -14, which is EFAULT.
Expected for a random argument to mkdir()

-Andi