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Why is memory being allocated before malloc code has run?


An initial heap is allocated to the process by the OS when the process is loaded; if an allocation cannot be satisfied the heap is extended by requesting more memory from the operating system.

See http://duartes.org/gustavo/blog/post/anatomy-of-a-program-in-memory/ for an explanation for example.

What you are seeing is the initial heap allocation to the process, not the total memory allocated by the process from that heap.


Categories : C

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