Commands using sed (1,319)

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Jump to a directory, execute a command and jump back to current dir

Make vim open in tabs by default (save to .profile)
I always add this to my .profile rc so I can do things like: "vim *.c" and the files are opened in tabs.

Add temporary entry to authorized_keys
If you frequently need to connect to your ubersecure mainframe from various uberunsafe machines, you have to face difficult decision: (a) type the password everytime during the session (lame), (b) add local public key to mainframes authorized_keys file (unsafe), (c) as above, but remove this key at the end of the session (pain in the a55). So let's say you save The Command to tempauth file in bin directory of your mainframe's account and make it executable. Then, while you're on one of these unsafe ones, do: $ cat $HOME/.ssh/id_rsa.pub|ssh 5z474n@mainframe.nl bin/tempauth 30 and password prompts stop the harassment for 30 minutes and you don't have to care to remove the unsafe key after that.

copy from host1 to host2, through your host
Good if only you have access to host1 and host2, but they have no access to your host (so ncat won't work) and they have no direct access to each other.

Swap a file or dir with quick resotre
This lets you replace a file or directory and quickly revert if something goes wrong. For example, the current version of a website's files are in public_html. Put a new version of the site in public_html~ and execute the command. The names are swapped. If anything goes wrong, execute it again (up arrow or !!).

Compare two CSV files, discarding any repeated lines
The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

Generate Random Text based on Length
Random text of length "$1" without the useless cat command.

Remove invalid host keys from ~/.ssh/known_hosts
Useful if you have to tunnel ssh through a local port and it complains of the host key being different. Much easier than manually editing the file.

find out how many days since given date
You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

Show all LISTENing and open server connections, with port number and process name/pid


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