A gargbage collector need not be conservative. Interestingly linux (and most posix compliant unices I guess) implements, as last resort, an actual tracing file descriptor garbage collector to track the lifetime of file descriptors: as they can be shared across processes via unix sockets (potentially recursively), arbitrary cycles can be created and reference counting is not enough.
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A gargbage collector need not be conservative. Interestingly linux (and most posix compliant unices I guess) implements, as last resort, an actual tracing file descriptor garbage collector to track the lifetime of file descriptors: as they can be shared across processes via unix sockets (potentially recursively), arbitrary cycles can be created and reference counting is not enough.