It is preferred to pass pointer to structure to a function in C -

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In general, to avoid copying during a function call, like to pass the structure of the pointer to a function in C is done. Its unwanted side effect is that the function function can modify the structure elements inadvertently. What is a good programming practice to avoid such errors without compromising the efficiency of the function call?

has an obvious-to-parent answer explicitly 

  void Foo (const struct some_struct * p)

This will prevent you from modifying members immediately Strat is unknowingly the same for the const .

In fact, your question looks like a copy-paste from the card, which has the expected answer to be const


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