---
title: proto_media_input
framework: kernel
role: symbol
role_heading: Type Alias
path: kernel/proto_media_input
---

# proto_media_input

## Declaration

```occ
typedef errno_t (*proto_media_input)(ifnet_t ifp, protocol_family_t protocol, mbuf_t packet, char *header);
```

## Parameters

- `ifp`: The interface the packet was received on.
- `protocol_family`: The protocol of the packet received.
- `packet`: The packet being input.
- `header`: The frame header.

## Return Value

Return Value If the result is zero, the caller will assume the packet was passed to the protocol. If the result is non-zero and not EJUSTRETURN, the caller will free the packet.

## Discussion

Discussion proto_media_input is called for all inbound packets for a specific protocol on a specific interface. This function is registered on an interface using ifnet_attach_protocol.