kernel keeps returning a clos() error

the close() function keeps returning -9/9 according to the kernel...does that mean -1 or does that mean something else???

a computer has lead to this problem
let the computer solve it

if(-9 == -1) printf("-1 means -9");

Try

Code:

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if (close(fp) != 0)
{
  perror ("close");
}

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