Checking for null before pointer usage

Question

Most people use pointers like this...

if ( p != NULL ) {
  DoWhateverWithP();
}

However, if the pointer is null for whatever reason, the functi

Answer 1

When you check for NULL, it is not good idea just to skip the function call. You should have an else-part that does something meaningful in case of NULL, for example throws an error or returns error code to upper level.

On the other hand, NULL is not always an error. It is often used to indicate for example that end of data has been reached. In such case, you will have to handle the situation as normal program flow.