Messages in this thread | | | From | "Perez-Gonzalez, Inaky" <> | Subject | RE: System Call parameters | Date | Wed, 16 Apr 2003 17:39:36 -0700 |
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> From: Richard B. Johnson [mailto:root@chaos.analogic.com] > > 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.
I use %ebp, it seemed to work last time I played with it:
static inline int st_mmap (void *addr, size_t len, int protection, int flags, int fd, off_t offset) { int result; asm volatile ( "pushl %%ebp \n" "movl %6, %%ebp \n" "movl %7, %%eax \n" "int $0x80 \n" "popl %%ebp \n" : "=a" (result) : "b" (addr), "c" (len), "d" (protection), "S" (flags), "D" (fd), "m" ((offset >> PAGE_SHIFT)), "i" (__NR_mmap2) : "memory"); return result; }
I thing I got it from an straight disassemble dump of glibc's mmap().
Iñaky Pérez-González -- Not speaking for Intel -- all opinions are my own (and my fault) - 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/
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