Commands by goodevilgenius (13)

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Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

show git commit history

bash or tcsh redirect both to stdout and to a file
When plumbers use pipes, they sometimes need a T-joint. The Unix equivalent to this is 'tee'. The -a flag tells 'tee' to append to the file, rather than clobbering it. Tested on bash and tcsh.

Show the power of the home row on the Dvorak Keyboard layout
Quick and dirty command that counts how many words can be typed just using the home row on the Dvorak Simplified Keyboard layout from a dictionary file, in this case /usr/share/dict/words. According to the regular expression supplied, each word must contain all the keys on the Dvorak home row, and no other characters. For comparison, I've shown how many words are installed in my dictionary, how many can be typed with just the Dvorak home row and how many can be typed with just the QWERTY home row in the sample output. Nearly 10 times the amount. If you want to see the words, remove the -c switch, and each word will be printed out.

Change to $HOME - zsh, bash4
To change to $HOME in that manner you need to set a shell option. In zsh it is auto_cd, hence $ setopt -o auto_cd in bash4 it is autocd, hence $ shopt -s autocd What the option does is allow you to cd to a directory by just entering its name. This also works if the directory name is stored in a variable: $ www=/var/www/lighttpd; $www sends you to /var/www/lighttpd. CAUTION: If a command or function name identical to the directory name exists it takes precedence.

Turn On/Off Keyboard LEDs via commandline
Usefull as a light blink to remember events, mails, intrusions, etc... yet another output Since nobody ever uses the scroll lock function... Usefull to interface a linux system with some hardware, for example, opto interfacing the keyboard led to a relay to remotely reset, etc. ( a simple LDR glued over the LED will do the trick ) xset led 3 turns on the third led, ie, Scroll lock xset -led 3 turns it off xset led 1 turns on Numerical Lock led ( doesn t work on all computer ) xset led 2 turns on Caps Lock led ( idem ) Using it as a reset watchdog, the relay expected light pulses. Shall the computer hangs, the relay releases and reset the machine ( discharge of a capacitor ) ;-)

Delete more than one month old thumbnails from home directory
By time thumbnail images in ~/thumbnails take up too much space, this command will help deleting old ones. Find options explained: -type f : find files only, not directories -atime +30 : last accessed more than 30 days ago

ping as traceroute
This command uses ping to get the routers' IP addresses to the destination host as traceroute does. If you know what I mean..

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.

get xclip to own the clipboard contents
"Copying" things to the X clipboard doesn't normally create a copy. Rather the data to be 'copied' is referenced. This means that if the application that you 'copied' stuff from is closed, that data is lost. If the application that you 'copied' from is suspended with CTRL-Z, there could be some issues if you try to paste it into something. This command will create a copy of referenced data and have xclip be the provider of it, so you can then go ahead and close the app that contains the original information. Caveat: I'm not sure if this is binary-safe (though i would expect it to be), and don't know what would happen if you used it to clip a 20 meg gimp image. This technique becomes more convenient if you set it up as an action in a clipboard manager (eg klipper, parcellite). Some of these applets can take automatic action based on a variety of parameters, so you could probably just get it to always own the clipped data whenever data is clipped.


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