Systémová volání ve Windows
Win32 -> NTDLL.DLL -> interrupt 0x2e (KiSystemService
export of ntoskrnl.exe) nebo SYSENTER/SYSEXIT resp.
SYSCALL/SYSRET (KiFastCallEntry)
#include <stdio.h>
int main() {
const char *myString="Hello!\n";
__asm{
push myString
call printf
pop eax
}
return 0;
}
Systémová volání Linux
nastavení EAX, … a zavolání int 0x80 nebo (od v2.5)
SYSENTER/SYSEXIT resp. SYSCALL/SYSRET
mov edx,8 ;message length
mov ecx,myString ;message to write
mov ebx,1 ;file descriptor (fd 1 is stdout)
mov eax,4 ;system call number (number 4 is sys_write)
int 0x80 ;call kernel
; Kernel call return value is in eax-- it'll do as a function return code.
ret
myString:
db 'Wazzup?',0xa ; our little string, followed by a newline