Date: Wed, 4 Sep 1996 22:58:59 -0300
Message-Id: <1.5.4.16.19960904200613.38df0bae@dmeasc.rc.ipt.br>
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To: "x DOT pons AT cc DOT uab DOT es" <ILGES AT cc DOT uab DOT es>, djgpp AT delorie DOT com
From: Cesar Scarpini Rabak <csrabak AT dce03 DOT ipt DOT br>
Subject: Re: Declaring global arrays in a multisource project

At 17:33 04/09/96 +0000, x DOT pons AT cc DOT uab DOT es wrote:
>Dear programmers,
>
>In a multi-source project I have a global array, declared as:
>
>  char my_global_array[256];
>
>in one of the modules.
>
>Which is the best way of declaring it on the other modules?
>
>  extern char my_global_array[256];
>  extern char *my_global_array;
>  extern char my_global_array[];
>
>Thanks,
>
>XP
Of the three, the first and third are OK, the second is technically wrong.
From a maintenance standpoint the third would easy your job if after a time
you change your mind about the size of my_global_array in the module where
it is defined (i,e. where memory is actually allocated for it). The third
form is legal ANSI C because "the declaration is not a defining ocurrence"
in ISO/ANSI C parlance.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Cesar Scarpini Rabak                      E-mail: csrabak AT ipt DOT br
DME/ASC                                   Phone: 55-11-268-35221Ext.350
IPT - Instituto de Pesquisas Tecnologicas Fax:   55-11-268-5996
Av. Prof. Almeida Prado, 532.  Sao Paulo - SP 05508-901 BRAZIL
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