how do i override a pointer to avoid memory leak

[olwethumlimi]

e.g

char *  message;
 message = tgc_alloc(&gc, 10); // it allocate
 strcpy(message, "test"); 
 message ="update" // override the value, 

[RolandMarchand]

In your example at line 4, the pointer from line 2 became unreachable., since message is now pointing at the string literal "update". The memory allocated at line 2 will be freed automatically.

If you're really concerned about memory leaks, you can run tgc_free() on the original pointer.