A struct may be more complex than an array, but it's perfectly possible to pass it as value, and it may be inefficient, but the reason that you can't pass an array by value is because it is defined as a pointer by default.

How do you pass a structure to a function?

Passing struct by reference

You can also pass structs by reference (in a similar way like you pass variables of built-in type by reference). We suggest you to read pass by reference tutorial before you proceed. During pass by reference, the memory addresses of struct variables are passed to the function.

Can you pass structs by value?

A struct can be either passed/returned by value or passed/returned by reference (via a pointer) in C. The general consensus seems to be that the former can be applied to small structs without penalty in most cases.