You have copies of everything in the forked processes, but those are the images taken from the moment you fork. After the fork, each process has its own memory space.

Although it is possible to share memory among processes, there are lots of articles about why it is not a good approach. For new applications, that is not a choice, unless you are touching some low level stuff.

Thread is the solution. Start to use threads, I say this to myself all the time. Let’s always ask ourselves the question whether thread is a good fit, whenever we are thinking of fork. My opinion is: use thread for tight coupling, and fork for loose coupling.

In your current case, you want to share a hash, I see it tight enough for threads. If there is other reasons unknown to me made you pick fork, go IPC’s, don’t use shared memory.

In reply to Re: communication between forked processes by pg
in thread communication between forked processes by gnu@perl

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