Casting diff structures to char*

[Robert Angelino]

I've written a function that takes a char* pointer to different
structs that have a common named var (which I'm accessing in this
function).  I've included an example.

struct one
{
 int a,
     rnum;
};

struct two
{
 char b;
 int a,
     rnum;
};

my_func(rec,...)
	char	*is_this_correct;
		.
		.
		.
{
is_this_correct->rnum = ...

}

my_func((char*) &a,...);
my_func((char*) &b,...);


This is the error I'm getting
"nonunique name demands struct/union or struct/union pointer".

I keep getting this error in my_func where I try to access rec->rnum.
Am I doing this correctly??

Thanks in advance and any suggestions are welcome.

-- 
    -     ------       -                              Robert Angelino
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