how to run C function in iphone SDk?

i have added one .h a开发者_StackOverflow社区nd .c file ,but i want to call the function which is in .c file from viewController?any help?if i add .h file and call that function linker error comes?

You need to add the ".c" file to your Xcode project, and you need to make sure that it is checked off in Xcode. If you make sure it is checked, then the source file should be linked into your project correctly.