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Adding Color Escape Codes to global CC array for use by echo -e
I was looking for the fastest way to create a bunch of ansi escapes for use in echo -e commands throughout a lot of my shell scripts. This is what I came up with, and I actually stick that loop command in a function and then just call that at the beginning of my scripts to not clutter the environment with these escape codes, which can wreck havok on my terminal when I'm dumping the environment. More of a cool way to store escape ansi codes in an array. You can echo them like: $ echo -e "${CC[15]}This text is black on bright green background." I usually just use with a function: $ # setup_colors - Adds colors to array CC for global use $ # 30 - Black, 31 - Red, 32 - Green, 33 - Yellow, 34 - Blue, 35 - Magenta, 36 - Blue/Green, 37 - White, 30/42 - Black on Green '30\;42' $ function setup_colors(){ declare -ax CC; for i in `seq 0 7`;do ii=$(($i+7));CC[$i]="\033[1;3${i}m";CC[$ii]="\033[0;3${i}m";done;CC[15]="\033[30;42m"; export R='\033[0;00m';export X="\033[1;37m"; }; $ export -f setup_colors CC[15] has a background of bright green which is why it is separate. R resets everything, and X is my default font of bright white. $ CC[15]="\033[30;42m"; R=$'\033[0;00m'; X=$'\033[1;37m' Those are just my favorite colors that I often use in my scripts. You can test which colors by running $ for i in $(seq 0 $((${#CC[@]} - 1))); do echo -e "${CC[$i]}[$i]\n$R"; done See: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html for more usage.

Makefile argument passing
This would allow reference of $(VAR) (if defined) with the value 'foobar' within the Makefile.

Silently deletes lines containing a specific string in a bunch of files
This command will find all occurrences of one or more patterns in a collection of files and will delete every line matching the patterns in every file

Rename files in batch

Send keypresses to an X application
This is a (last resort) way to automate applications that provide no other ways for automation, it would send 'Hello world' to the currently active window. See the manpage (and the -text and -window entries) for how to send special characters and target specific windows. An example: Using xwininfo, I get the id of my XPlanet background window: alanceil@kvirasim:19:51:0:~> xwininfo xwininfo: Please select the window about which you would like information by clicking the mouse in that window. xwininfo: Window id: 0x3600001 "Xplanet 1.2.0" Absolute upper-left X: 0 (..etc..) Now I use xvkbd to tell it to close itself: xvkbd -xsendevent -window 0x3600001 -text "Q" Obviously, the best way is to put these commands in a shellscript - just make sure to include a short sleep (sleep .1 should suffice) after each xvkbd call, or some programs will become confused.

convert pdf into multiple png files
syntax for resolution is: (see "man gs" for further informations) -rnumber -rnumber1xnumber2

grep (or anything else) many files with multiprocessor power
xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.

set a reminder for 5 days in the future
setup for reminder in 5 days, added the date in the future. To run a job at 4pm three days from now, you would do at 4pm + 3 days, to run a job at 10:00am on July 31, you would do at 10am Jul 31 and to run a job at 1am tomorrow, you would do at 1am tomorrow.

Count number of Line for all the files in a directory recursively

SVN script for automatically adding and deleting files


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