Hi > On 5 Feb 2024, at 17:02, Brooks Davis <bro...@freebsd.org> wrote: > > >>> 2. It simplifies the implementation of restrictions on system calls such >>> as those implemented by OpenBSD's msyscall(2) >>> (https://man.openbsd.org/msyscall.2). >> >> That's one to ignore for tools that make syscalls outside of the libc memory >> mapping. > > Should someone implement msyscall(2) there will certainly be an opt out > mechanism along the usual lines that uses elfctl and procctl.
I was thinking more of simply not passing on such syscalls. > >>> 3. It allows language runtimes to link with libsys for system call >>> implementations without requiring libc. >> >> I see that pagesize is on the list of functions that are moving. There are a >> couple of other functions that might cause me problems if libc isn't linked. >> >> Could you do a quick test with an exe linked to libsys but not libc running >> under Valgrind memcheck, please? > > Could you suggest a more concrete example? I don’t think that it really matters. Just an empty main(). The important thing would be linking to libsys and not libc. A+ Paul
