> On Mon, 23 Aug 1999, Mehta, Hiren wrote:
>
> > Can anybody explain the following complicated assembly that I found
> > include/asm-i386/unistd.h file ?
> >
> > #define _syscall0(type,name) \
> > type name(void) \
> > { \
> > long __res; \
> > __asm__ volatile ("int $0x80" \
> > : "=a" (__res) \
> > : "0" (__NR_##name)); \
> > if (__res >= 0) \
> > return (type) __res; \
> > errno = -__res; \
> > return -1; \
> > }
>
> _syscall0(foo_t, foo) expands into approximately:
> foo_t foo(void)
> {
> long result;
>
> /* make the call */
> result=call_interrupt_vector_0x80(__NR_foo);
>
> if(result>=0) return (foo_t) result;
>
> errno=result;
ITYM errno=-result; :)
>
> return -1;
> }
>
-- Mike <rickettm@ox.compsoc.net>When we are planning for posterity, we ought to remember that virtue is not hereditary. -- Thomas Paine
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