Today marks Day 1 of my 30-Day Coding Challenge to master C internals, Algorithms, and Database design.
Why am I doing this? In a world of AI and high-level abstractions, understanding how memory works under the hood is what separates a coder from an engineer. I want to build that foundational strength.
Today's Concept: The Array Lie; We often think of arrays as rigid lists. In C, the variable name of an array is actually just a pointer to the first element.
As shown in the snippet, numbers[1] is really just a human-readable way of writing *(numbers + 1). The computer adds the size of the data type to the base address to find the value.
Follow along for the next 29 days as I document my deep dive into system internals and optimization.
📂 View the source code on GitHub: [https://github.com/Ujjawal0711/30-Days/tree/main]
Top comments (1)
Not quite. For
numbers, there is no pointer anywhere in that program nor its memory. For there to be an actual pointer, there would need to be 8 bytes (assuming a 64-bit system) set aside somewhere that contains the address of the array. That's not reality.The correct way to say it is: the name of an array "decays" into the address of its first element as if it were a pointer to it.
Note that there is an exception: when the name of an array is used as an argument to
sizeof, it returns the size of the entire array, not the size of a pointer.