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# fdtype

The file descriptor type, as a libproc type.

```
var fdtype: UInt32
```

## Discussion

If this value is `PROX_FDTYPE_PIPE`, the [`es_fd_t`](/documentation/EndpointSecurity/es_fd_t) structure also contains a `pipe.pipe_id` field. This field represents the unique ID of the pipe for correlation with other file descriptors pointing to the same or other end of the same pipe.

---

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