Commands by pepin (10)

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Encrypt and password-protect execution of any bash script, Version 2
(Please see sample output for usage) Use any script name (the read command gets it) and it will be encrypted with the extension .crypt, i.e.: myscript --> myscript.crypt You can execute myscript.crypt only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Sorry for the chmod on parentheses, I dont like "-" at the end. Thanks flatcap for the subshell abbreviation to /dev/null

Run TOP in Color, split 4 ways for x seconds - the ultimate ps command. Great for init scripts
One of my favorite ways to impress newbies (and old hats) to the power of the shell, is to give them an incredibly colorful and amazing version of the top command that runs once upon login, just like running fortune on login. It's pretty sweet believe me, just add this one-liner to your ~/.bash_profile -- and of course you can set the height to be anything, from 1 line to 1000! $ G=$(stty -g);stty rows $((${LINES:-50}/2));top -n1; stty $G;unset G Doesn't take more than the below toprc file I've added below, and you get all 4 top windows showing output at the same time.. each with a different color scheme, and each showing different info. Each window would normally take up 1/4th of your screen when run like that - TOP is designed as a full screen program. But here's where you might learn something new today on this great site.. By using the stty command to change the terminals internal understanding of the size of your terminal window, you force top to also think that way as well. # save the correct settings to G var. $ G=$(stty -g) # change the number of rows to half the actual amount, or 50 otherwise $ stty rows $((${LINES:-50}/2)) # run top non-interactively for 1 second, the output stays on the screen (half at least) $ top -n1 # reset the terminal back to the correct values, and clean up after yourself $ stty $G;unset G This trick from my [ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html bash_profile ], though the online version will be updated soon. Just think what else you could run like this! Note 1: I had to edit the toprc file out due to this site can't handle that (uploads/including code). So you can grab it from [ http://www.askapache.com/linux-unix/bash-power-prompt.html my site ] Note 2: I had to come back and edit again because the links weren't being correctly parsed

Get HTTP status code with curl AND print response on new line

Do a search-and-replace in a file after making a backup

Sort installed rpms in alphabetic order with their size.

Make directory including intermediate directories
This will create the intermediate directories that do not exist. I did not know about this for a long time.

Analyse an Apache access log for the most common IP addresses
This uses awk to grab the IP address from each request and then sorts and summarises the top 10.

Show which process is blocking umount (Device or resource is busy)
Instead of using force un-mounting, it's better to find the processes that currently use the relevant folder. Taken from: http://www.linuxhowtos.org/Tips%20and%20Tricks/findprocesses.htm

Arguments too long

Capitalize first letter of each word in a string
Capitalize first letter of each word in a string.


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