why won't the following compile?
 

Hi. what am I doing wrong here. >

#include <stdio.h>
int copy(int a);

int main(void)
{

int num = 5;
int c = 0;

c = copy(num);

printf("num = %d\n", c);

return 0;
}
int copy(int a)
{

int a = num;

return a;
}


gcc gives me the following errors but since I am fairly new I don't understand them


copy.c: In function `copy':
copy.c:19: warning: declaration of `a' shadows a parameter
copy.c:19: `num' undeclared (first use in this function)
copy.c:19: (Each undeclared identifier is reported only once
copy.c:19: for each function it appears in.)

it says 'num' is undeclared but I decalred it in 'main' ...

thanks :)

it's a scope issue, copy() can't see your num variable, num is local to main() move num outside of main to make it global or add int num inside of copy().

thanks :) havent got to scope yet but I think I know what you mean

I think you are redfining "int a" in copy. Scope issue is also involved. So the local int shadows the "int a" defined in copy(int a). Try this.

int copy(int a)
{
return a;
}

--Sarin

int copy(int num)
{
int a;
return a=num;
}

I think thats what you are trying to do! :)