centralized auth and nsswitch.conf
Matthew Dillon
dillon at apollo.backplane.com
Fri Jul 25 13:58:44 PDT 2003
:I'm missing something here.
:
:The underlying communication mechanism is LWKT in the kernel.
:
:UserAPI communicates with the kernel through a LWKT-compatible gate.
:
:UserAPI uses LWKT messages as its own intermediate abstractions.
:
:So, this would mean taking a LWKT message, encapsulating it into
:something that can be passed over a stream, taking that stream
:and encapsulating it into a LWKT message, and then passing it
:into the kernel and finally back to the receiving application
:where it's unpacked back to a stream and then to the encapsulated
:LWKT message.
:
:I see a real use for the ability to talk more directly from one
:user context to another using LWKT messages, presumably by
:specifying a different message port (fd?) in the 0x81 syscall.
What the LWKT messaging gives us in this case is an abstraction that
fits well with the userland threading infrastructure, allowing things
like asynchronous queries when most existing APIs (like gethostbyname())
are synchronous-only. But this capability should not be confused
with the basic transport mechanism used to communicate the messages
between processes. I would far prefer that a normal, portable IPC
mechanism be used for the transport because it allows us to create
a portable standard that other UNIXes can use whether or not they
implement the end points as LWKT messages.
-Matt
Matthew Dillon
<dillon at xxxxxxxxxxxxx>
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