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May 19, 2015 - A Look At The New Commandlinefu
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Remove a line in a text file. Useful to fix

Terminal - Remove a line in a text file. Useful to fix
ssh-keygen -R <the_offending_host>
2010-07-11 19:37:24
User: bunam
Functions: ssh ssh-keygen
Remove a line in a text file. Useful to fix

In this case it's better do to use the dedicated tool


There are 3 alternatives - vote for the best!

Terminal - Alternatives
sed -i 8d ~/.ssh/known_hosts
sed -i 3d ~/.ssh/known_hosts
2011-05-26 11:34:03
User: evandrix
Functions: sed

deletes line 3 in known_hosts text file

> ~/.ssh/known_hosts
2010-08-04 06:54:18
User: cde1985

This is the quick and dirty alternative ;)

The whole file will be emptied, this is equal to /dev/null > ~/.ssh/known_hosts

echo "${1}" | egrep '^[[:digit:]]*$' ; if [ "$?" -eq 0 ] ; then sed -i "${1}"d $HOME/.ssh/known_hosts ; else printf "\tYou must enter a number!\n\n" ; exit 1 ; fi
2010-07-11 23:09:11
User: DaveQB
Functions: echo egrep exit printf sed
Tags: sed

I have this as a file called deletekey in my ~/bin.

Makes life a little easier.

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