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From: kimcm@rimfaxe.diku.dk (Kim Christian Madsen)
Newsgroups: comp.lang.c
Subject: Re: FILE *fp[]; /* is this possible? */
Message-ID: <1990Nov29.153505.27783@diku.dk>
Date: 29 Nov 90 15:35:05 GMT
References: <1990Nov27.131327.21662@agate.berkeley.edu> <1990Nov28.152146.19560@ssd.kodak.com>
Sender: news@diku.dk (The Netnews System)
Organization: Department Of Computer Science, University Of Copenhagen
Lines: 18

weimer@ssd.kodak.com (Gary Weimer) writes:

>for(i=0;i!=256;i++)
>    if ((fp[i]=fopen(file_name[i],"r+")) <= 0)  /* some will probably     */
>                                                /* complain about using   */
>						 /* <= 0                   */

YES, for more than one reason:


	1) fopen returns a FILE * and should be tested against the constant
	   NULL, or (FILE *) NULL if you want explicit casting.

	2) If the pointer returned by fopen points to a memory location in
	   the high end it is very possible that when converted to an int
	   for the comparison it will be negative.

						Kim Chr. Madsen