Path: utzoo!attcan!uunet!husc6!uwvax!rutgers!mailrus!uwmcsd1!bbn!bbn.com!levin
From: levin@bbn.com (Joel B Levin)
Newsgroups: comp.sys.mac.programmer
Subject: Re: LSC 3.0, argc & argv, linking
Message-ID: <29449@bbn.COM>
Date: 8 Sep 88 14:21:23 GMT
References: <66791@sun.uucp> <2391@pixar.UUCP> <59@calmasd.GE.COM>
Sender: news@bbn.COM
Reply-To: levin@BBN.COM (Joel B Levin)
Organization: BBN Communications Corporation
Lines: 32

In article <59@calmasd.GE.COM> jnp@calmasd.GE.COM (John Pantone) writes:
|
|Are you saying that ThinkC and Unix will not allow something like:
|
|link my_main with (my_)printf and anything else needed from lib c
|(except the copy of printf in there)
|
|where the printf explicitly specified also exists in lib c, but I wish
|it to be superceeded by my version?
|
|Then the ThinkC and the Unix linker are outmoded and weak, to say the
|least.  REAL linkers have allowed this sort of selective replacement
|for years. . . .

The UNIX(TM) linkers I have known, and the MPW linker as well, do
allow exactly this.  But there is one problem that you have to watch
out for.  Using your example: if the module within the library which
contains printf also contains (say) sprintf, AND my_main calls sprintf
as well as printf, AND you do not provide a substitute (my_)sprintf,
then when the linker attempts to resolve the sprintf reference, it
will find itself with two entries for printf.  This will make it
unhappy.  The solution is to determine all the entry points in the
standard library module containing printf and to provide those entry
points in your own version.

As to the previous question: sorry, I have no idea what ThinkC does.

	/JBL


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