There is a good explanation for why the file handles are shared but the buffers are not. The buffering is done by Perl, in the IO layer, so each process gets its own memory and buffers. The low-level read is done by the OS, and it shares the file handle. There is a cache in the OS, but that doesn't have any behavior effect on the processes, other than the read being faster.

In reply to Re^4: Unexpected output from fork (Win32) by iburrell
in thread Unexpected output from fork (Win32) by maa

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