Find when new hardware is connected on FreeBSD

All other answers are good, if you want only to check if a device is connected (checking kernel messages with dmesg, check in /var/log files and use some tools like usbconfig, pciconf or camcontrol).

But, if you want more (handle a message and execute a program or something like that when you plug your device), you can use devd.

When you connect a device, FreeBSD kernel will generate messages:

• when you plug your device, an attach message is generated
• when you unplug your device, a detach message is generated
• and more (see devd.conf man page if you want more information).

FreeBSD uses devd by default, and its configuration is stored in /etc/devd/ and /etc/devd.conf. If you use linux, the same features exist with devfs and udev.

You can find some examples in /usr/share/examples/etc/devd.conf.

dmesg | grep -i USB will give you the list of connected

To get information about USB devices. usbconfig can help give it a try.

or

pciconf -lv pciconf diagnostic utility for the PCI bus