Messages in this thread | ![/](/images/icornerl.gif) | | From | "H. Peter Anvin" <> | Subject | Re: System Call parameters | Date | 16 Apr 2003 13:35:37 -0700 |
| |
Followup to: <Pine.LNX.4.53.0304161256130.11667@chaos> By author: "Richard B. Johnson" <root@chaos.analogic.com> In newsgroup: linux.dev.kernel > > How does the kernel get more than five parameters? > > Currently... > eax = function code > ebx = first parameter > ecx = second parameter > edx = third parameter > esi = fourth parameter > edi = fifth parameter > > Some functions like mmap() take 6 parameters! > Does anybody know how these parameters get passed? > I have an "ultra-light" 'C' runtime library I have > been working on and, so-far, I've got everything up > to mmap() (in syscall.h) (89 functions) working. > I thought, maybe ebp was being used, but it doesn't > seem to be the case. >
%ebp is used.
However, on i386, SYS_mmap is a four-parameter system call where the last parameter is a pointer to a parameter block. SYS_mmap2 is the full six-parameter sane version.
You may want to check out klibc.
-hpa
-- <hpa@transmeta.com> at work, <hpa@zytor.com> in private! "Unix gives you enough rope to shoot yourself in the foot." Architectures needed: ia64 m68k mips64 ppc ppc64 s390 s390x sh v850 x86-64 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| ![\](/images/icornerr.gif) |