NG_DEVICE(4)

💖 NG_DEVICE 💖

okay bestie, welcome to the manual page for ng_device — that's the device netgraph node type, from the Kernel Interfaces Manual section 4. sit down, grab a boba, we're gonna get you fluent in this fr fr 🧋✨

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✨ NAME ✨

ng_device — the device netgraph node type 💅

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🌸 SYNOPSIS 🌸

#include <netgraph/ng_device.h>

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🦋 DESCRIPTION 🦋

So a device node is literally two things at once, no cap: it's a netgraph node and a system device interface. main character energy honestly 👑

The way that when a device node gets created, a whole new device entry just appears — and you can reach it with all your regular file operators like open(2), close(2), read(2), write(2), etc. iconic behaviour, we love to see it 💖

And the naming? Obsessed. The first node shows up as /dev/ngd0, and then every subsequent one is /dev/ngd1, /dev/ngd2, etc. — just counting up forever like a little queue of cuties 🎀

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🫶 HOOKS 🫶

A device node has a single hook, and you can give it any arbitrary name you want. Slay, freedom of expression 💅

Here's the tea on the data flow:

• everything coming in over the hook gets presented to the device for read(2) 📥
• everything coming in from the device entry via write(2) gets forwarded to the hook 📤

it's giving two-way street, it's giving communication, it's giving 🦋

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🔥 CONTROL MESSAGES 🔥

This node supports exactly one non-generic control message, and here she is:

• NGM_DEVICE_GET_DEVNAME — returns the device name that corresponds to a node ✨

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💀 SHUTDOWN 💀

This node shuts down when:

• it receives a NGM_SHUTDOWN control message, or
• the hook gets disconnected 😭

And when that happens, the associated device entry is removed and becomes available for use by future device nodes. recycling queen ♻️✨

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👑 SEE ALSO 👑

• netgraph(4)
• ngctl(8)

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🌈 HISTORY 🌈

The device node type was first implemented in FreeBSD 5.0. a legend was born, periodt 💅

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🎀 AUTHORS 🎀

• Mark Santcroos <marks@ripe.net>
• Gleb Smirnoff <glebius@FreeBSD.org>

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and that's the whole page bestie!! this one's from the Debian crew, dated October 19, 2004, and it's page NG_DEVICE(4) in section 4 — go forth and netgraph responsibly, ily, mwah 💖🦋🌸