ref: 54366e8a221b4fc485eae0b376fee39ec897d1ca
dir: /syscall-osx.s/
.globl _std$syscall
_std$syscall:
popl %ecx /* return address */
popl %eax /* call num */
pushl %ecx
int $0x80
pushl %ecx /* put the return address back */
ret