Question

I have grep function in C( embedded programming ) that takes a void pointer as a parameter. the function needs to be able to handle different kinds of types of variables like chars ints and longs. How can I code the function so it can figure out by itself what type of variable i am passing ?? I dont know if this is possible. thanks

ie.

void grep( void *t ) 
{ 
   if( t == char ) 
   { 
      do this 
   } 
   if( t == int ) 
   { 
      do that  
   }  
   ... 
}

Answer 1

It is not possible to do with any accuracy. A 4 byte integer could easily be interpreted as a string for example. For example, a null terminated string “ABC” would be the same as the integer value 1094861568 (depending on byte order).