Re: Calling libraries from assembler.

"H. Peter Anvin"  <spamtrap@[EMAIL PROTECTED]
> writes:
>SoLo2 wrote:
>> Hello!
>> 
>> 
>> I have tried how simple it is to use
>> system calls in Linux from assembler.
>> Setting parameters in the registers
>> eax/edx and then "int 0x80".
>> 
>> I would like to know it there
>> is a similar, easy way of calling
>> other libraries (specially X windows).
>> 
>> It should be as simple as giving
>> the function name in ASCII ! :)
>> 
>
>On 32-bit x86:
>
>	/* foo = func(arg1, arg2, arg3) */
>
>	push arg3
>	push arg2
>	push arg1
>	call func
>	mov %eax,foo
>
>On 64-bit x86:
>
>	mov arg3,%rdx
>	mov arg2,%rsi
>	mov arg1,%rdi
>	call func
>	mov %rax,foo
>
>	-hpa
>

Although the x86 part does get a bit more complicated after the first 6
args,
for floating args, and for arguments that don't fit in a 64-bit register.

See the x86_64 processor ABI for full details.

 <http://www.linux-foundation.org/spec/refspecs/elf/x86_64-SysV-psABI.pdf>

scott