check struct.member for being empty first
Code:
if(struct.member!=NULL)   //make sure not un-initialised
{  // do other checks here
   if(str_cmp(struct.member,"same_text")==0)
   {
      // they are the same - so do something
   }
}

and first usage of struct member MUST be a
Code:
struct.member = str_create("something");  //is now now initialised
I also assume you are using str_cpy() and str_cmp() and not strcpy() and strcmp()
because they ARE different...

"There is no fate but what WE make." - CEO Cyberdyne Systems Corp.
A8.30.5 Commercial