iwevent

iwevent [interface]

interface
    Wireless interface name (e.g., wlan0) to monitor events on. Defaults to first detected wireless interface if unspecified.

iwevent is a utility from the wireless-tools package that displays real-time wireless events from the Linux kernel for specified network interfaces. It captures kernel-reported changes such as:

• Association/disassociation with access points
• Signal strength and noise level updates
• Link quality fluctuations
• Bitrate changes
• ESSID or frequency shifts

These events help troubleshoot Wi-Fi connectivity, monitor roaming, or trigger scripts based on network state.

The tool runs continuously, polling the kernel via the Wireless Extensions ioctl interface (e.g., SIOCGIWPRIV, event socket) and formats output with timestamps for readability. Example: 2024-01-15 10:23:45.123 New link status: Connected to 00:11:22:33:44:55.

Primarily used on older systems with Wireless Extensions API support. For modern setups, prefer iw event due to nl80211 compatibility.

Legacy tool relying on obsolete Wireless Extensions API; fails on nl80211-only drivers (most modern Wi-Fi chipsets). No output without active events; lacks filtering or verbose modes.

wlan0 2024-01-15 14:30:12.456 Close link with AP aa:bb:cc:dd:ee:ff cell aa:bb:cc:dd:ee:ff
wlan0 2024-01-15 14:30:13.012 New link status: Connected to aa:bb:cc:dd:ee:ff (essid 'MyNetwork')
wlan0 2024-01-15 14:30:13.789 Signal level=-42 dBm Noise level=-92 dBm

Part of wireless-tools by Jean Tourrilhes, first released ~1996-2000. iwevent added early 2000s for event dumping. Declined with kernel 2.6.32+ shift to cfg80211/nl80211; unmaintained since ~2010.

iwconfig(8), iwlist(8), iwspy(8), iw(8)