Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!netcom!hue
From: hue@netcom.UUCP (Jonathan Hue)
Newsgroups: comp.sys.amiga
Subject: Re: Apple System 7.0
Summary: Not so (Mach does it)
Message-ID: <1247@netcom.UUCP>
Date: 17 May 89 03:38:21 GMT
References: <24279@agate.BERKELEY.EDU> <6834@cbmvax.UUCP> <751@boing.UUCP>
Organization: NetCom Services - Public Access Unix System (408) 997-9175 guest
Lines: 22


In article <751@boing.UUCP>, dale@boing.UUCP (Dale Luck) writes:
>  
> This is a simple message passing mechanism that is completely 
> inadequate for any ipc between machines. For this a bidirectional byte 
> stream is needed that does not rely ptrs to buffers. The data itself must  
> be passed. So if you are interested in networks with this amiga ipc you need 
> to forget amiga Messages. 

Mach allows you to pass messages over a network.  If you don't specify inline
data in the message header, the receiver gets a pointer to it rather than the
data.  Until the message is actually touched by the recipient (which will
generate a page fault), the data is not copied from the sending machine.
This fits in with Mach's philosophy of supporting large, sparse address
spaces.  Mach message passing is not a bidirectional byte stream, though with
inline data you can make it behave like one.

IMHO, Mach message passing is superior to BSD sockets.  If you haven't
looked at Mach, it might be worthwhile to see an alternative to the BSD
kernel.

-Jonathan