The time has come for a kernel interfacing library layer

Matthew Dillon dillon at
Sat May 7 16:23:46 PDT 2005

:Matthew Dillon wrote:
:>     The kernel loader (and ld-elf
:>     when it loads things) will automatically detect the existance of the
:>     section and automatically mmap() the actual syscall layer into the 
:>     BSS space, as well as mmap() anything else that it needs for system
:>     interfacing (any additional mmap()'d sections will be not be directly
:>     visible to userland.  Userland only sees the stub table).
:Can I safely assume here that you mean it'll load 'old defaults' for 
:programs not carrying around that specific bss data section?
:		-- Thomas E. Spanjaard
:		   tgen at xxxxxxxxxxxxx

    Well, the layering is the *only* way we can really support backwards
    and forwards compatibility.  We can retrofit 1.2-RELEASE's dynamic
    binaries with the layer by adding it to libc as a TEXT section 
    containing all the system calls so if the kernel doesn't override them
    it just reverts to the old hardwired system calls.  Older static 
    binaries are going to be more of a problem since they cannot be 

					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>

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