Shell Tips

How to see the full command for a given process?

env COLUMNS=200 ps -o pid,command

How to delete a specific line from a file?

# delete the line 18 from '~/.ssh/known_hosts' file
sed -i '18 d' ~/.ssh/known_hosts

# also
sed -i 18d ~/.ssh/known_hosts
 
# delete few lines
# delete 6 lines from line 8
sed -i 8,+6d file.txt 
 
# delete the line where is 'TO DELETE'
sed -i '/TO DELETE/ d' file.txt

How to remove a wrong host key in SSH known_hosts file?

ssh-keygen -R hostname

-- JakubMoscicki - 05 Oct 2006