Code for malloc and free

c linux malloc free
MetallicPriest picture MetallicPriest · Jun 26, 2011 · Viewed 37.9k times · Source

Where can I find the code for malloc my gcc compiler is using at the moment? I actually want to write my own malloc function which will be a little different from the original one. I know I can use hooks et all, but I want to see the real code.

Answer

Cédric Julien picture Cédric Julien · Jun 26, 2011

The POSIX interface of malloc is defined here.

If you want to find out how the C library in GNU/Linux (glibc) implements malloc, go and get the source code from http://ftp.gnu.org/gnu/glibc/ or browse the git repository and look at the malloc/malloc.c file.

There is also the base documentation of the Memory Allocator by Doug Lea that describes the theory of a m(emory)alloc(ator) (read this carrefully, and then decide if you really need to implement your own malloc).

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