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### 2.2 Simple Example

Here is a trivial example that calls `puts` a few times.

    #include <stdio.h>
    #include <ffi.h>

    int main()
    {
      ffi_cif cif;
      ffi_type *args[1];
      void *values[1];
      char *s;
      ffi_arg rc;

      /* Initialize the argument info vectors */
      args[0] = &ffi_type_pointer;
      values[0] = &s;

      /* Initialize the cif */
      if (ffi_prep_cif(&cif, FFI_DEFAULT_ABI, 1,
    		       &ffi_type_sint, args) == FFI_OK)
        {
          s = "Hello World!";
          ffi_call(&cif, puts, &rc, values);
          /* rc now holds the result of the call to puts */

          /* values holds a pointer to the function's arg, so to
             call puts() again all we need to do is change the
             value of s */
          s = "This is cool!";
          ffi_call(&cif, puts, &rc, values);
        }

      return 0;
    }