Help required for usermod command

Hi,

I would need to modify my machine name :
When i give "w" command, i am getting following message

USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
krishnag pts/59 gunasekar 1:25pm 25:15 0.03s 0.03s -csh.

My questions is, i need to change FROM (i.e machine name): "gunasekar" to
"Gunaseelan"

Is there any command changing my machine names using usermod command?

How should i do that? Can anyone help me?

Thanks,
Guns.

I would need to modify my machine name :
When i give "w" command, i am getting following message

USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
krishnag pts/59 gunasekar 1:25pm 25:15 0.03s 0.03s -csh.

My questions is, i need to change my machine name: "gunasekar" to
"Gunaseelan".

Can anyone help?