Specifically, how does fork() handle dynamically allocated memory from malloc() in Linux?

Question

I have a program with a parent and a child process. Before the fork(), the parent process called malloc() and filled in an array with some data. After the fork(), the chil

Answer 1

The short answer is 'dirty on write' - the longer answer is .. a lot longer.

But for all intends and purposes - the working model which at C level is safe to assume is that just after the fork() the two processes are absolutely identical -- i.e. the child gets a 100% exact copy -- (but for a wee bit around the return value of fork()) - and then start to diverge as each side modifies its memory, stack and heaps.

So your conclusion is slightly off - child starts off with the same data as parent copied into its own space - then modifies it - and see s it as modified - while the parent continues with its own copy.

In reality things are bit more complex - as it tries to avoid a complete copy by doing something dirty; avoiding to copy until it has to.

Dw.