$9.$ Rewrite the two functions shown below so they are no longer vulnerable to a buffer overflow attack. Don$$t use any $$safe$$ libraries in your solution.

int copy$\_$buf $($ char $*$to $,$ int pos $,$ char $*$ from $,$ int len $)$

$\{$

int i; for $($i $=0$; i $<$ len ; i $++)\{$

to $[$ pos $]=$ from $[$i $]$;

pos $++$;

$\}$

return pos ;

$\}$

short read$\_$chunk $($ FILE fil $,$ char $*$ to $)$

$\{$

short len ;

fread $($& len $,2,1,$ fil $)$;

fread $($to $,1,$ len $,$ fil $)$;

return len ;

$\}$