KwickClips C++ · 42 sec · free
Why use a new pointer for realloc?
Short answer. It may fail and return NULL.
How many times do you free a block?
Exactly once.
realloc and free
| realloc keeps old values |
| Save its result in a new pointer |
| free each block exactly once |
Remember
| realloc resizes |
| free gives memory back |
Two more students joined. How do you grow the block? Use realloc. It keeps the old values. Save its result in a new pointer, since it may fail. Then free each block once. Remember this. Realloc resizes. Free gives memory back.
This clip is from the full lesson: Dynamic Memory Allocation: malloc, calloc, realloc and free — 6 minutes, with the tables, the quick answers and the whole lesson in text.
Useful for: Programming All levels C
More KwickClips from this lesson
Disclaimer. KwickAcademy is free study material for general learning and revision. Parts of it, including the voice-over, are produced with the help of AI tools and may contain errors; if you spot one, please tell us and we will correct it. Syllabus, marks and exam details follow the latest official board publications available to us, and boards can change them at any time, so always confirm against your board's official website and your school. Using this material does not guarantee any marks or result. Board names and trademarks belong to their owners; Kwickprep is not affiliated with or endorsed by any examination board. We never ask for passwords, OTPs or ID numbers. Your progress is saved only in this browser. Full disclaimer · Privacy