Linux x86-64bit kernel interface ABI and mmap.

[oblique]

Hello,

I found that i have to use r10 for the 4th argument of mmap syscall. I read Appendix A of ABI and it says:

User-level applications use as integer registers for passing the sequence
%rdi, %rsi, %rdx, %rcx, %r8 and %r9. The kernel interface uses %rdi,
%rsi, %rdx, %r10, %r8 and %r9.

Why mmap use kernel interface?
Is there any other syscalls that use it?


thanks.

PS: sorry for my bad english...

[oblique]

i found what means... user-level is when you call a function form shared object and kernel-interface is when you call syscalls