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Create a new file

Prepend a text to a file.
Using the sed -i (inline), you can replace the beginning of the first line of a file without redirecting the output to a temporary location.

Analyze awk fields
Breaks down and numbers each line and it's fields. This is really useful when you are going to parse something with awk but aren't sure exactly where to start.

add the result of a command into vi
':r!ls -l' results in listing the files in the current directory and paste it into vi

watch process stack, sampled at 1s intervals
This command repeatedly gets the specified process' stack using pstack (which is an insanely clever and tiny wrapper for gdb) and displays it fullscreen. Since it updates every second, you rapidly get an idea of where your program is stuck or spending time. The 'tac' is used to make the output grow down, which makes it less jumpy. If the output is too big for your screen, you can always leave the 'tac' off to see the inner calls. (Or, better yet--get a bigger screen.) Caveats: Won't work with stripped binaries and probably not well with threads, but you don't want to strip your binaries or use threads anyway.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Get a BOFH excuse
Gets a BOFH excuse from the BOFH excuse server (towel.blinkenlights.nl port 666), and passes it through sed and tr to get rid of telnet connection stuff.

cat ~/.ssh/id_rsa.pub | ssh user@site.com "cat - >> ~/.ssh/authorized_keys"
You'll want to use this for passwordless logins. Same as ssh-copy-id, if you don't have it on your system.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Regex to remove HTML-Tags from a file
This regular expression removes all HTML-Tags from the file.


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