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Randomly run command
Randomly decide whether to run a command, or fail. It's useful for testing purposes. . Usage: ran PERCENTAGE COMMAND [ARGS] Note: In this version the percentage is required. . This is like @sesom42 and @snipertyler's commands but in a USABLE form. . e.g. In your complicated shell script, put "ran 99" before a crucial component. Now, it will fail 1% of the time allowing you to test the failure code-path. $ ran 99 my_complex_program arg1 arg2

Find the package that installed a command

Create executable, automountable filesystem in a file, with password!
This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it. USAGE: SEE SAMPLE OUTPUT The file is composed of three parts: a) The legible script (about 242 bytes) b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242) c) The actual filesystem Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option. PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :) It applies the original idea of http://www.commandlinefu.com/commands/view/7382/command-for-john-cons for encrypting the file. The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables.

Rename files in batch

list block devices
Shows all block devices in a tree with descruptions of what they are.

Use find to get around Argument list too long problem
Can be used for other commands as well, replace rm with ls. It is easy to make this shorter but if the filenames involved have spaces, you will need to do use find's "-print0" option in conjunction with xargs's "-0" option. Otherwise the shell that xargs uses to execute the "rm" command line will treat the space as a token separator, thereby treating the name as two (or more) names.

repeat a command every one second
Short method of "while x=0; do foo ; sleep 1 ; done"

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Get curenttly playing track in Last.fm radio

Print Memory Utilization Percentage For a specific process and it's children
Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.


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