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Write copy_string that copies source into destination when capacity is non-zero, always terminates the destination, and reports failure if the source will not fit.
cat, capacity 41Write down the input contract and the failure cases before coding.
Ready to run the file open above against 2 tests.
The destination needs room for every source byte plus the terminator, so the fit check is length < capacity. Copying through index <= length deliberately includes '\0'; writing an empty string on failure leaves a predictable destination state.
your-solution.c.solution.c only after a real attempt.This intermediate C exercise focuses on Buffer capacity, Size-bounded copying, API return contracts. Its requirements define the exact behavior to implement before you write code.
Start with the displayed example input and expected output, then test a boundary case suggested by the requirements. Open your-solution.c and select Run code. The browser uses the same safe C subset as the C course, including a test harness for exercise functions.
Attempt Copy a string with a capacity contract first. Then open the read-only solution file to compare the contract, edge-case handling, and implementation choices—not simply to copy the final code.