Commands by ajrobinson (2)

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recursive search and replace old with new string, inside files
If you can install rpl it's simpler to use and faster than combinations of find, grep and sed. See man rpl for various options. time on above operation: real 0m0.862s, user 0m0.548s, sys 0m0.180s using find + sed: real 0m3.546s, user 0m1.752s, sys 0m1.580s

Split and join with split and cat.
`split -b 1k file` splits files into 1k chunks. Rejoin them with `cat x* > file`.

Pull Total Memory Usage In Virtual Environment
This command basically adds up all of the individual instances processes and gives you a grand total for used memory in that instance alone.

Generate a random password 30 characters long

search installed files of package, that doesn't remember his name well. On rpm systems
rpm, sometimes, is not wildcard friendly. To search files installed from package this could be useful. change PACKAGENAME to any package do you want to search

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.

Play all files in the directory using MPlayer
Skip forward and back using the < and > keys. Display the file title with I.

get the latest version
to download latest version of "util", maybe insert a sort if they wont be shown in right order. curl lists all files on mirror, grep your util, tail -1 will gets the one lists on the bottom and get it with wget

Reset hosed terminal,
stty sane resets the tty to basic usable function. The ^J is a newline -- sometimes CR/LF interpretation is broken so use the ^J explicitly.

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"

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