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Go (cd) directly into a new temp folder
This command create a new temp directory using mktemp (to avoid collisions) and change the current working directory to the created directory.

Delete empty directories with zsh
This command uses the recursive glob and glob qualifiers from zsh. This will remove all the empty directories from the current directory down. The **/* recurses down through all the files and directories The glob qualifiers are added into the parenthesis. The / means only directories. The F means 'full' directories, and the ^ reverses that to mean non-full directories. For more info on these qualifiers see the zsh docs: http://zsh.dotsrc.org/Doc/Release/Expansion.html#SEC87

make a log of a terminal session
Creates a log of a session in a file called typescript. Or specify the file with: $script filename Exit the session with control-d.

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

extract email adresses from some file (or any other pattern)
This will catch most separators in the section of the email: dot . dash - underscore _ plus + (added for gmail) ... and the basic dash '-' of host names.

create disk copy over the net without temp files
I wanted to create a copy of my whole laptop disk on an lvm disk of the same size. First I created the logical volume: lvcreate -L120G -nlaptop mylvms SOURCE: dd if=/dev/sda bs=16065b | netcat ip-target 1234 TARGET: nc -l -p 1234 | dd of=/dev/mapper/mylvms-laptop bs=16065b to follow its process you issue the following command in a different terminal STATS: on target in a different terminal: watch -n60 -- kill -USR1 $(pgrep dd) (see http://www.commandlinefu.com/commands/view/4356/output-stats-from-a-running-dd-command-to-see-its-progress)

Typing the current date ( or any string ) via a shortcut as if the keys had been actually typed with the hardware keyboard in any application.
That works in all softs, CLI or GUI... I don't want to waste time to all the time typing the same stuff . So, I have that command in my window manager shortcuts ( meta+l ). All the window managers have editable shortcuts AFAIK. If not, or you don't want to use it that way, you can easily use the xbindkeys soft. I you're using kde4, you can run : $ systemsettings then open "inputs actions" and create a new shortcut. For Gnome take a look there : http://www.cyberciti.biz/faq/howto-create-keyboard-shortcuts-in-gnome/ A more advanced one, with strings and newlines : $ xvkbd -xsendevent -text "---8

write the output of a command to /var/log/user.log... each line will contain $USER, making this easy to grep for.
This command is useful if you want to copy the output of a series of commands to a file, for example if you want to pastebin the output from 'uname -a', 'lspci -vvv' and 'lsmod' for video driver trouble-shooting on your favorite Linux forum. 'log' takes all the following arguments as a command to execute, with STDOUT sent to /var/log/user.log. The command is echoed to the log before it is executed. The advantages of using logger (as opposed to appending output from commands to a file) are 1) commands are always appended to the logs... you don't have to worry about clobbering your log file accidentally by using '>' rather than '>>' 2) logs are automatically cleaned up by logrotate. The following functions allow you to mark the start and end of a section of /var/log/user.log. $ startlog() { export LOGMARK=$(date +%Y.%m.%d_%H:%M:%S); echo "$LOGMARK.START" | logger -t $USER; } then $ endlog() { echo "$LOGMARK.END" | logger -t $USER; } printlog will print all lines between $LOGMARK.START and $LOGMARK.END, removing everything that is prepended to each line by logger. $ printlog() { sudo sed -n -e "/$LOGMARK.START/,/$LOGMARK.END/p" /var/log/user.log| sed "s/.*$USER: //"; } The following command should dump just about all the information that you could possibly want about your linux configuration into the clipboard. $ startlog; for cmd in 'uname -a' 'cat /etc/issue' 'dmesg' 'lsusb' 'lspci' 'sudo lshw' 'lsmod'; do log $cmd; done; endlog; printlog | xsel --clipboard This is ready for a trip to http://pastebin.com/, and you don't have to worry about leaving temporary files lying around cluttering up $HOME. Caveats: I'm sure that startlog, endlog, and printlog could use some cleanup and error checking... there are unchecked dependencies between printlog and endlog, as well as between endlog and startlog. It might be useful for 'log' to send stderr to logger as well.

Convert a file from ISO-8859-1 (or whatever) to UTF-8 (or whatever)
I use it sometimes when I work on a french file transferred from a windows XP to a Debian-UTF8 system. Those are not correctly displayed: ? ? ? and so on $man tcs # for all charsets

Change the homepage of Firefox
This command modifies the preferences file of Firefox that is located in .mozilla/firefox/*.default/prefs.js. It edits the file with sed and the -i option. Then it searches the string "browser.startup.homepage", and the string next to it (second string). Finally, it replaces the second string with the new homepage, that is http://sliceoflinux.com in the example. It doesn't work if you haven't set any homepage.


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