Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!virtech!cpcahil
From: cpcahil@virtech.UUCP (Conor P. Cahill)
Newsgroups: comp.sys.ibm.pc
Subject: Re: why does this compare fail in TC2.0?
Keywords: C question about compares in turbo c 2.0
Message-ID: <1085@virtech.UUCP>
Date: 29 Aug 89 00:56:37 GMT
References: <127@cica.cica.indiana.edu>
Distribution: na
Organization: Virtual Technologies Inc
Lines: 23

In article <127@cica.cica.indiana.edu>, burleigh@cica.cica.indiana.edu (Frank Burleigh) writes:
> 1. in a test file that has some missings, the compare fails every time,
>    even though i can see via tc's watch that fld actually holds ".," with
>    NULL in fld[2].  thus, execution always drops through to the else
>    clause.  i *have* a different version:
>  
>        if( fld[0] == '.' && fld[1] == ',' ) ...
>  
>    which works correctly.    why does the compare fail?

Because C comparisons only work on scalar values.  the compare that 
you were using is actually comparing the pointer fld to the address
of the ".," constant (this should never be true).





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