--- title: "Custom Device Paths with UDEV rules" date: 2020-11-10T20:58:37-05:00 draft: false tags: ["Linux"] medium_enabled: true --- I wanted to create a rule so that when I plug in my rtlsdr, a symlink to the device will appear in `/dev/rtlsdr`. To do this, first we need to get some uniquely identifying information about the SDR. ```bash ❯ lsusb Bus 001 Device 002: ID 8087:8001 Intel Corp. Integrated Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 002 Device 017: ID 0bda:2838 Realtek Semiconductor Corp. RTL2838 DVB-T Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub ``` The part we care about here is the ID field. It is structured as `ID vendor:product`. Now we can create a UDEV rule in `/etc/udev/rules.d/` that says "when we see this specific USB plugged in, create a symlink called `rtlsdr`" (/etc/udev/rules.d/rtlsdr.rules) ``` SUBSYSTEM=="usb", ATTR{idVendor}=="0bda", ATTR{idProduct}=="2838", SYMLINK+="rtlsdr" ``` Tell udev to reload its rules ```bash sudo udevadm control --reload ``` Now once you have your device plugged in, you should be able to see it under `/dev/rtlsdr` or whatever you specified your symlink as.