Re: (interposers): How to workaround the "strong symbols" problem?

In article <wwvsepessby.fsf@LkoBDZeT.terraraq.uk>,
Richard Kettlewell  <invalid@invalid.invalid> wrote:
...

System call can mean two things:
>
1) The actual transfer to the kernel, via an instruction such as SYSCALL
  (x86) or SVC (Arm). This is what appears in strace.
2) The function in the C library that contains this instruction.
>
Normally the distinction is irrelevant, but here it matters.
>
You cant interpose a syscall, is only true for sense 1. That
instruction is somewhere the middle of a function and the interposition
technique hes using relies on runtime symbol resolution rules, so it
doesnt apply to sense-1 syscalls.

When I wrote "syscall", I meant (surprisingly enough) syscall.
What you are calling "sense #1".

So, what I wrote is correct.

What you are calling "sense #2" (i.e., the "glibc wrapper" that is provided
for most (not all) syscalls) is just another function and can, of course,
be interposed.

--
Watching ConservaLoons playing with statistics and facts is like watching a
newborn play with a computer.  Endlessly amusing, but totally unproductive.