[ILUG] math.h and sqrt() function

[Colm Buckley]

> I have included math.h, I have even searched to see if I was including
> the wrong one, but I can't find another.
> 
> So could anyone please tell me why I get when I compile:
> [phil at jalapeno src]$ gcc mathtest.c
> /tmp/ccVM9ceB.o: In function `main':
> /tmp/ccVM9ceB.o(.text+0x38): undefined reference to `sqrt'
> /tmp/ccVM9ceB.o(.text+0x6b): undefined reference to `sqrt'
> collect2: ld returned 1 exit status

sqrt() is in the maths library "libm.so".  Add the "-lm" flag to gcc to
tell it to link with this library.

gcc -o mathtest mathtest.c -lm

            Colm

-- 
Colm Buckley B.A. B.F. <colm at tuatha.org> | <colm.buckley at cs.tcd.ie>
Department of Computer Science      # +353 87 2469146 # whois cb3765
Trinity College, Dublin 2, Ireland. # http://www.tuatha.org/~colm/
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