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Date:   Thu, 28 May 2020 11:48:13 -0400
From:   "Bruno Dantas" <dantas@airpost.net>
To:     linux-wireless@vger.kernel.org
Subject: iwlist scanning: how to exclude old scan results from output?
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I hope it's not too inappropriate to ask a support question here. I've tried at my distro's forum to no avail.

Please, how do I make "sudo iwlist <iface> scanning" display only results from current scan? Cached prior scan results (including no-longer-available hotspots) often show up in the output, which breaks one of my shell scripts.

If iwlist does not include an option to ignore old scan results, a workaround would be to first flush the results of old scan, then scan. The problem is that I can't figure out where prior scan results stored. Surely one of you guys would know? The only way I've found to flush old scan results is to unload then reload the wireless interface's kernel module, but this approach seems heavy-handed when a simple "cat /dev/null > somefile" might be sufficient if I knew where old scan results are kept.

Thanks a million for any insights.

-Bruno

P.S. Here are some possibly relevant details about my system:
  - OS: Tiny Core Linux 11 64-bit
  - linux kernel version: 5.4.3
  - wireless card: Atheros AR928X
  - wireless driver: ath9k
  - iwlist version: 29