Export Command — Intended Effect?

Question

In the FAQ article on aMSN, it states that if you have aMSN to "hang up" often and you have configured all of your sound options correctly to try running aMSN with this command: export LD_ASSUME_KERNEL=2.2.5 && amsn

Now, my question is what effect will this have on my system? I am a Linux newbie, so I am not sure how my system will react and if this command is a good idea.

If this export will affect only aMSN, then I am all for giving it a shot. But seeing the nature of Linux commands (rm -rf anyone?) and how disastrous and unforgiving they can be if you don't know what you're doing, I am reluctant to try it, even if it was from an 'official' source. I do not want to lose performance or something similar just to make aMSN work -- I'd rather just take the occasional hang for aMSN.

Answer 1

export LD_ASSUME_KERNEL=2.2.5 is setting a shell environment variable $LD_ASSUME_KERNEL to 2.2.5. Programs use the environment variables to help configure various aspects of themselves (like the $TERM variable for the shell indicates what type of terminal it should emulate) and can be relatively harmless. (I say can be because some variables are important, like the $PATH variable and $PS1)

If you want to see if $LD_ASSUME_KERNEL is set before running aMSN, open a terminal (like Konsole or Terminal) and type echo $LD_ASSUME_KERNEL at the prompt. If a blank line is produced $LD_ASSUME_KERNEL is unset and aMSN defaults to its settings and setting it will let aMSN do whatever it will do with that variable. If it is set, then you'll be replacing whatever was there with 2.2.5 when you run aMSN.

Off the top of my head I don't immediately recognize the LD_ASSUME_KERNEL variable so I believe you should be safe running it. If something does happen you can always reboot since the export command by itself doesn't persist across reboots. (The system and personal profile scripts set those up on every boot and login)