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Display connections histogram
Displays a connection histogram of active tcp connections. Works even better under an alias. Thanks @Areis1 for sharing this one.

Display 16 largest installed RPMs in size order, largest first
Interesting to see which packages are larger than the kernel package. Useful to understand which RPMs might be candidates to remove if drive space is restricted.

Umount only the NFS related to 'string'
Sometimes, you have a lot of NFS in the server and you can't or shouldn't use umount -a. Whis this command, you only umount the fs related to the 'string'

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Create and play an instant keyword based playlist
It works best as part of a function, such as the following: MUSICROOT=~/Music function fplay { if [ $1 = '-v' ]; then shift 1 find -E $MUSICROOT -type f -iname "*$**" -iregex '.*\.(3g[2|p]|aac|ac3|adts|aif[c|f]?|amr|and|au|caf|m4[a|r|v]|mp[1-4|a]|mpeg[0,9]?|sd2|wav)' -print -exec afplay "{}" \; & else find -E $MUSICROOT -type f -iname "*$**" -iregex '.*\.(3g[2|p]|aac|ac3|adts|aif[c|f]?|amr|and|au|caf|m4[a|r|v]|mp[1-4|a]|mpeg[0,9]?|sd2|wav)' -exec afplay "{}" \; & fi }

Execute a command at a given time

Print a row of characters the width of terminal
Unlike other methods that use pipes and exec software like tr or sed or subshells, this is an extremely fast way to print a line and will always be able to detect the terminal width or else defaults to 80. It uses bash builtins for printf and echo and works with printf that supports the non-POSIX `-v` option to store result to var instead of printing to stdout. Here it is in a function that lets you change the line character to use and the length with args, it also supports color escape sequences with the echo -e option. $ function L() { local l=; builtin printf -vl "%${2:-${COLUMNS:-`tput cols 2>&-||echo 80`}}s\n" && echo -e "${l// /${1:-=}}"; } With color: $ L "`tput setaf 3`=" 1. Use printf to store n space chars followed by a newline to an environment variable "l" where n is local environment variable from $COLUMNS if set, else it will use `tput cols` and if that fails it will default to 80. 2. If printf succeeds then echo `$l` that contains the chars, replacing all blank spaces with "-" (can be changed to anything you want). From: http://www.askapache.com/linux/bash_profile-functions-advanced-shell.html http://www.askapache.com/linux/bash-power-prompt.html

split a multi-page PDF into separate files
Simple alternative to the previous submitted one

Empty a file

Get the full path of a bash script's Git repository head.
Rather than complicated and fragile paths relative to a script like "../../other", this command will retrieve the full path of the file's repository head. Safe with spaces in directory names. Works within a symlinked directory. Broken down: $cd "$(dirname "${BASH_SOURCE[0]}")" temporarily changes directories within this expansion. Double quoted "$(dirname" and ")" with unquoted ${BASH_SOURCE[0]} allows spaces in the path. $git rev-parse --show-toplevel gets the full path of the repository head of the current working directory, which was temporarily changed by the "cd".


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