Will: objective c can call the standard c library.

As the title: in xcode compiler can call the c standard library in objective-c in?
If possible, please suggest specific operation, or give a sample source.
Thank you!
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Directly on the line
With the use of C as
C + +, then it should. M changed. Mm file
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Of course you can.
Objective-C is a superset of C99.
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Is not available on all standard c library, such as math.h, another in xcode in that position to see these standards c library
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I tried, you can use such as pow () and other such functions, but did not see anywhere explicitly import these libraries are not included when Hou I had included a good foundation for the