From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Mon, 15 Apr 1996 13:45:09 -0400
From: Boyd Roberts boyd@france3.fr
Subject: ioctl
Topicbox-Message-UUID: 43aef16e-eac8-11e9-9e20-41e7f4b1d025
Message-ID: <19960415174509.qSZXnJtlhntOg_8DF-ggYU1F-A4qWDdg-cE6rJ5scgg@z>

    From: Min Huang <mhuang@CS.Cornell.EDU>

    I am porting a system built on the top of Unix to Plan9.
    Because the system use ioctle to get network address, network configuration,
    I find that plan9 doesn't support SIOCGIFADDR and SIOCFIFCONF.
    Could you please tell me how I can modify the plan9 to make it support them.

i think you'll find the idea is not to modify plan 9, but your system.
getting rid of ioctl was a feature.