On Wed, 11 Nov 2020 11:02:14 -0800 Cong Wang <xiyou.wangc...@gmail.com> wrote:
> On Tue, Nov 10, 2020 at 8:32 PM 杜英杰 <leon...@pku.edu.cn> wrote: > > > > I want to use inotify to monitor /sys/class/net//operstate to detect > > status of a iface in real time. > > when I ifdown && ifup eth3, the content of operstate changed, but > > the file's Modify time didn't change. > > I don't know the reason, is there any file which can be monitored by > > inotify to get iface status in real time? > > Much appreciation for any advice! > > You need to listen to netdev netlink messages for changes like > this. These messages are generated in real-time. The /sys and /proc are pseudo-filesystems. The file modify time and inotify do not work as expected on these files. Cong is right you need to use netlink for this.
