The advantage of system_profiler is that it allows finer control over the output.

The POSIX utility system_profiler is the command-line equivalent of the System Profiler application that runs when you select 'About This Mac' from the Apple menu, and click the 'More Info.' button in the resulting dialog. While there is no perfect solution to this problem, it's easy to take a first step that will eliminate most of the threat. What you need is some sort of warning that the topology of the USB bus has changed unexpectedly. Physical detection isn't reliable, because as noted above the device may look just like a component you already have, such as an extension cable, or may be hidden inside a keyboard enclosure or out of sight behind a desktop computer. Therefore, if you detect the keylogger before the attacker comes back for it, you can defeat the attack. The attacker who installed it has to return to retrieve the device or the data. The weakness of the hardware keylogger, at least the kind that's available on the open market, is that it's not remotely accessible. It works just as well on a Mac as on a Windows box. The device is completely self-contained and platform independent, needing no software to operate apart from its own firmware. Once installed, it automatically begins to capture all keystrokes into its internal NVRAM, which may be up to 2MB in capacity. A keylogger may be physically indistinguishable from a USB extension cable or some other innocuous device. Some actually function as USB hubs that can be connected anywhere in the bus. A hardware keylogger is a small, inconspicuous USB device that can be hot-plugged into any computer between the keyboard and the host controller. Hardware keylogging devices create serious issues for all security-conscious computer users.

Anti keylogger mac os x