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From: bc@uxa.cso.uiuc.edu (Ben Cox)
Newsgroups: comp.unix.programmer
Subject: Re: C libraries
Message-ID: <1991Jan3.115324.7357@ux1.cso.uiuc.edu>
Date: 3 Jan 91 11:53:24 GMT
References: <1990Dec19.232345.1397@dayton.saic.com> <1990Dec23.230945.10473@xrtll.uucp> <7774@umd5.umd.edu>
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xialin@umd5.umd.edu (Xia Lin) writes:


>I would like to use some math functions in <math.h> in my C program (in unix).
> The compiler keeps telling me that "undefined:   _exp, _sqrt", even though I
> have included a "#include <math.h>" statement at the begining of my program. 
>What did I do wrong? Do I need to use some compiler options like "cc -?" for using library functions?
>Thanks in advance for any helps.

cc foo.c -lm
         ^^^ This is the important part -- link in the math library.

--
-- Ben Cox
bc@uxa.cso.uiuc.edu