C Buffer Problem?

[pakixd]

I'm having issues with a program I'm developing for a class. It is a Lucas Number calculation program that requires a pipe and fork to be used. The source code for the file can be found at <link removed>

Can anyone help me out? here's the output I'm getting:

Create the pipe

Enter a number: 10
Create the child process using fork
parent is running...
about to write to the pipe
after writing to the pipe

child is running...
about to read from the pipe
after reading from the pipe
the value of n is: 10
the value in the buffer is: Writing to

fib( 0) = 0
Calculating...elapsed time = 8
fib( 1) = 1072693248
Calculating...elapsed time = 9
fib( 2) = 1072693248
Calculating...elapsed time = 10
fib( 3) = 1073741824
Calculating...elapsed time = 11
fib( 4) = 1074266112
Calculating...elapsed time = 12
fib( 5) = 1075052544
Calculating...elapsed time = 13
fib( 6) = 1075838976
Calculating...elapsed time = 14
fib( 7) = 1076494336
Calculating...elapsed time = 15
fib( 8) = 1077215232
Calculating...elapsed time = 16
fib( 9) = 1078001664
Calculating...elapsed time = 17
{cs1:~/unix} fib(10) = 1078689792

I admit I'm a total noob to C so any help would be greatly appreciated. The program is compiled on a Sun Solaris server and is running there. Here's the definition for lucas numbers: http://en.wikipedia.org/wiki/Lucas_prime

Thank you!

[pakixd]

Code:

// includes stdio and time libraries
 
float    fib(int);
int    fork(void);
void   sleep(unsigned);
 
int main(void)
{
   int n; // input variable
   int i; // for the loop
   int start = time(NULL); // get the time the process started
        char buf[100]; /* store the characters read */
 
   // pipe needs an integer array of size 2
        int fd[2];
        printf("Create the pipe\n\n");
        pipe(fd); /* fd[0] read; fd[1] write */
 
 
    printf("Enter a number: ");
    scanf("%d", &n)
        printf("Create the child process using fork\n");
   if (fork() == 0) {    // child process
        close(fd[1]); /* close write end */
        printf("child is running...\n");
        printf("about to read from the pipe\n");
        n = read( fd[0], buf, 100); /* child reads from pipe */
        printf("after reading from the pipe\n");
        printf("the value of n is: %d\n",n);
        printf("the value in the buffer is: %s\n\n", buf);
      for (i = 0; i <= n; ++i) {
         printf("fib(%2d) = %d\n", i, fib(i));
         sleep(1);
        }
    }
   else    {            // parent process
        close(fd[0]); /* close read end - not needed for this example */     
        printf("parent is running...\n");
        printf("about to write to the pipe\n");
        write( fd[1], "Writing to pipe\n", n); /* parent writes to pipe */
        printf("after writing to the pipe\n\n");
     for (i = 0; i < n; ++i) {
         sleep(1);
         printf("Calculating...elapsed time = %d\n", time(NULL) - start);
      }
    }
   return 0; // exits program
}
 
float fib(int n) // fibonacci function, recursive
{
   if (n <= 1)
      return n;
   else
      return (fib(n - 1) + fib(n - 2));
//float fi = (1 + sqrt(5))/2;
  //return (pow(fi,(float)n) - pow(-fi,-(float)n))/sqrt(5);
}

Note currently im trying to debug this using the fibonacci recursive function but i need it to do lucas numbers, which is the commented code in the line at the end