The same assembly code but different result on cygwin and Centos

The same assembly code but different result on cygwin and Centos

[matthew chao]

The code below assigns an integer number 20 to %ebx,  which  can be
CORRECTLY assembled on both cygwin and CentOS,

###code begin###
.section .data
items:
.long  20

.section .text
.globl _start
_start:
  movl $0,%edi
  movl items(,%edi,4),%eax
  movl %eax,%ebx

  movl $1,%eax
  int $0x80
###code end###
However, when I wanted to get the number(20) by the following way, I
found  the difference between cygwin and CentOS,

cygwin:
------------------------------
  Matt@Matt-PC ~
$ ./max2

Matt@Matt-PC ~
$ echo $?
127                        # The result is WRONG
------------------------------

CentOS:
------------------------------
[Matt@localhost]# ./max2
[Matt@localhost]# echo $?
20                          # The result is RIGHT
------------------------------
Could someone give me a hand?thanks

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Re: The same assembly code but different result on cygwin and Centos

[Václav Haisman]

matthew chao wrote, On 26.4.2011 4:52:
> The code below assigns an integer number 20 to %ebx,  which  can be
> CORRECTLY assembled on both cygwin and CentOS,
> 
> ###code begin###
> .section .data
> items:
> .long  20
> 
> .section .text
> .globl _start
> _start:
>   movl $0,%edi
>   movl items(,%edi,4),%eax
>   movl %eax,%ebx
> 
>   movl $1,%eax
>   int $0x80
>[...]
Cygwin is Linux emulation DLL, it runs on top of Win32 API. It does not
emulate Linux' syscalls; it cannot emulate that.

-- 
VH

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