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From: dold@mitisft.Convergent.COM (Clarence Dold)
Newsgroups: comp.lang.c
Subject: Re: FILE *fp[]; /* is this possible? */
Message-ID: <1716@mitisft.Convergent.COM>
Date: 29 Nov 90 16:00:26 GMT
References: <14603@smoke.brl.mil>
Organization: Convergent Technologies, San Jose, CA
Lines: 20

in article <14603@smoke.brl.mil>, gwyn@smoke.brl.mil (Doug Gwyn) says:

> In article <1990Nov28.152146.19560@ssd.kodak.com> weimer@ssd.kodak.com (Gary Weimer) writes:
>>    if ((fp[i]=fopen(file_name[i],"r+")) <= 0)
>>        perror("Error opening file");

> Please don't do this; on UNIX, perror() will report the reason for the last
> SYSTEM CALL failure, not the reason for failure of a library routine such as

Quoth my man page, perror(3c):
"... last error encountered during a call to a system or library function..."

The most common coding error in this area is to check errno after calling
a function, without checking for an error return from the function, resulting
in retrieval of some earlier errno, not associated with more recent calls.
-- 
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