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From: boris@sftri.UUCP (B.Altman)
Newsgroups: net.lang.c
Subject: Re: Can #define `token-string' be empty?
Message-ID: <365@sftri.UUCP>
Date: Sat, 2-Mar-85 18:46:21 EST
Article-I.D.: sftri.365
Posted: Sat Mar  2 18:46:21 1985
Date-Received: Sun, 3-Mar-85 05:23:59 EST
References: <151@cci-bdc.UUCP> <282@cmu-cs-k.ARPA>, <363@sftri.UUCP> <5124@utzoo.UUCP>
Organization: AT&T Bell Laboratories, Summit N.J.
Lines: 24

> > This is not necessary on System V release 2 C compiler. You can omit extern
> > everywhere. ld will be able to handle those constructs.
> 
> It is necessary for portability, however -- something AT&T cares less
> and less about these days.  AT&T to the contrary, Vr2 is not the whole
> world.  Thank God.
> -- 
> 				Henry Spencer @ U of Toronto Zoology
> 				{allegra,ihnp4,linus,decvax}!utzoo!henry
 I guess I should put a disclaimer.
 The opinion presented here is my own and not of ATT or anyone else.

 The section 7.2 External data definitions of "Draft proposed C standard"
 indicates that you CAN omit "extern". When the standard gets acceptance,
 I do not think argument "standard is not the whole world" will be sufficient
 reason to "play tricks" just to be able to compile on some nonconforming
 C compiler.
 To give you just a bit of history, when Bell Labs were trying to enforce
 K&R rule on externs many people were very unhappy, since it broke
 a lot of code. That is why "multiple externs" were implemented in SVR2.

				Boris Altman
				AT&T Bell Labs, Summit NJ
				{ihnp4,ucbvax}!attunix!boris