Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!wuarchive!husc6!endor!siegel
From: siegel@endor.harvard.edu (Rich Siegel)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Passing pointers to functions (was Re: HLock)
Message-ID: <3508@husc6.harvard.edu>
Date: 29 Dec 89 00:46:16 GMT
References: <859@lclark.UUCP> <9389@hoptoad.uucp> <5832@umd5.umd.edu>
Sender: news@husc6.harvard.edu
Reply-To: siegel@endor.UUCP (Rich Siegel)
Organization: Symantec Language Products Group
Lines: 34

In article <5832@umd5.umd.edu> zben@umd5.umd.edu (Ben Cranston) writes:
>In article <859@lclark.UUCP> dan@lclark.UUCP (Dan Revel) writes:
>
>> Is it safe to pass pointers to functions
>> across segment boundaries?  (I think this question might be
>
>The other case is also worth considering.  Suppose you take a pointer to
>a local function (so the pointer generated is to the real function, not to
>a jump table entry).  You then pass this pointer to a function in another

	I don't know about other development systems, but if you take the
address of a function in THINK C or THINK Pascal, a jump table entry
gets generated for that function if one does not already exist. This is
to avoid exactly this sort of thing.

	Of course, you can take the absolute address of a local function
in assembly language, but that's your funeral...

R.




~~~~~~~~~~~~~~~
 Rich Siegel
 Staff Software Developer
 Symantec Corporation, Language Products Group
 Internet: siegel@endor.harvard.edu
 UUCP: ..harvard!endor!siegel

"When someone who makes four hundred and fifty dollars an hour wants to
tell you something for free, it's a good idea to listen."

~~~~~~~~~~~~~~~