Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!lll-winken!uunet!glyph!nichiren
From: nichiren@glyph.UUCP (Andy Heffernan)
Newsgroups: comp.sys.amiga.tech
Subject: Why 6 bytes between pointe to functions in *Base
Keywords: Pointer and Flags???
Message-ID: <0286.AA0286@glyph>
Date: 29 Mar 89 04:10:41 GMT
References: <2486@scolex.sco.COM>
Followup-To: comp.sys.amiga.tech
Distribution: na
Organization: Eh?
Lines: 28

Someone else will slip this in before me, but I'm a weasel.

In article <2486@scolex.sco.COM> brianm@sco.COM (Brian Moffet) writes:
> I noticed the other day that the distance between shared 
> library functions is 6 bytes.  The is at an offset less than 
> the base of the Shared Library pointer.  I would like to know,
> why 6 bytes?  4 of these bytes should be the pointer itself,
> but what are the other 2?  flags?

They are the 680x0 JMP instruction, $4EF9.
You do a lib call with something like:
	jsr $fdd8(a6)
which lands you into your jump table.
From there, this:
	jmp $2032ea
will get you to your library function.

Empiricism is fun, no?

> Brian Moffet			{uunet,decvax!microsoft,ucscc}!sco!brianm
>  -or-				...sco!alar!brian

A.Heffernan, weasel-at-large

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Andy Heffernan              uunet!glyph!nichiren            [1222 - 1282]
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