Value vs. Reference in C : When Do Function Modifications Affect the Calling Function?

Understanding Pass by Value and Reference in C

In C , it's crucial to comprehend the distinctions between passing by value and passing by reference.

Passing by Value

When passing by value, a new copy of the object is created and assigned to the function parameter. This means any changes made within the function to this copy will not affect the original object outside the function.

Passing by Reference

In contrast, passing by reference means the function parameter directly accesses the original object in memory. Modifications made within the function are reflected in the original object.

Understanding the Statement: "If the Function Modifies that Value, the Modifications Appear within the Scope of the Calling Function for Both Passing by Value and by Reference"

This statement may seem confusing initially. However, it's important to clarify that the word "value" in the statement refers to the object's data, not the object itself.

When passing by value, the function creates a copy of the object's data and assigns it to the parameter. If the function modifies this data, the original object's data is unaffected.

In contrast, passing by reference allows the function to access the original object's data directly. Any changes made to the data within the function modify the original object.

Therefore, regardless of whether a function passes an object by value or reference, if the function modifies the data within the object, those changes will be visible outside the function.

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