the bblog

annoyances

Hey, ho, Linux! Two things.

So I ssh into my home computer from work, right? Seeing as how it's sitting on a dynamically allocated IP address, ssh throws up an error every time the IP address changes. I usually ignore it, seeing as how I have nothing but contempt for best practices, but recently I decided to actually check the fingerprint against known_hosts.

Ha ha, sucker! Can't do that anymore!

Apparently, the point of known_hosts hashing is to prevent an attacker with access to your account from examining your known_hosts, and determining what other machines you have access to. There doesn't seem to be any way of viewing the known_hosts file in an un-hashed state, not that I tried very hard. It's a... pretty obscure vector, but the OpenBSD guys specialize in unusual attacks, so yeah.

Secondly, on the eee, firefox tends to step on amarok when doing heavy lifting, resulting in stuttering. There's presumably more subtle ways to deal with this, but I just renice amarok to -3 and firefox to 3. That turns out to be mildly difficult, thanks to some militantly unhelpful error messages. Behold:

/home/user> renice 1488 -3
renice: -3: bad value

It's not complaining about "-3", which is a valid priority, (0 is normal priority, 1 through 20 are progressively lower priorities, and -1 through -20 are progressively higher.) but 1488, which is the correct process number but a flamboyantly invalid priority, since renice wants the argument in the form of "priority" "proccess number".

This is somewhat of a non-issue, since -20 through 0 are invalid process numbers, and 1 through 20 are unlikely to be processes that a normal user wishes to change the priority of. But renice knows what it wants, no matter how vague its error messages may be.