Re: Programmatically get ethernet interface speed?

From: Jeff Garzik (
Date: Thu Jul 12 2001 - 10:37:23 EST

"Hen, Shmulik" wrote:
> Has anyone tested this interface with the below mentioned adapters ?
> I've had a bad experience with an AceNIC Gigabit copper. For some reason,
> when disconnecting the cable from a 1000Mbps switch, the speed does not drop
> to 0 as expected.

That is not expected.

The ethtool interfaces shows the phy media settings. We can certainly
add a ethtool "is carrier present?" ioctl, but it is not in the current

Currently, check the interface flags. netif_carrier_{on,off} will make
IFF_RUNNING disappear and re-appear.

In 2.5 and maybe later 2.4 too, netif_carrier_{on,off} will send a
netlink message indicating a carrier status change.

> I tried modifying the driver's code and adding debug
> prints and it looks like the adapter isn't reporting speeds correctly. I
> tried posting to but got no help there. Below is my
> original mail about the problem, please look at it and let me know if
> something can be done to correct the situation. (I really need a working
> EthTool interface working over an AceNIC ;-).

Given the above and the message you quoted below, it sounds like you are
misunderstanding the API, not that acenic is broken.


Jeff Garzik      | A recent study has shown that too much soup
Building 1024    | can cause malaise in laboratory mice.
MandrakeSoft     |
To unsubscribe from this list: send the line "unsubscribe linux-net" in
the body of a message to

This archive was generated by hypermail 2b29 : Sun Jul 15 2001 - 21:00:25 EST