Commands by prabhakaran9397 (2)

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Show DeviceMapper names for LVM Volumes (to disambiguate iostat logs, etc)
Emits the device names which will be printed by iostat for an LVM volume; doesn't show the names for the underlying devices when snapshots are being used (the -cow and -real devices in /dev/mapper)

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" }

Capitalize first letter of each word in a string - A ruby alternative
"-n" loops around ; "-e" executes the given quoted string ; "$_" is the current line ; "split" creates an array on white space; each item of the array is "collected" to be then "capitalized" ; the array is "joined" back into a 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"

Check your unread Gmail from the command line
Checks the Gmail ATOM feed for your account, parses it and outputs a list of unread messages. For some reason sed gets stuck on OS X, so here's a Perl version for the Mac: $ curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '' '{for (i=2; i

Place the argument of the most recent command on the shell
This works if your terminal is in Vi mode

Rapidly invoke an editor to write a long, complex, or tricky command
Next time you are using your shell, try typing $ ctrl-x ctrl-e # in emacs mode or $ v # in vi mode The shell will take what you've written on the command line thus far and paste it into the editor specified by $EDITOR. Then you can edit at leisure using all the powerful macros and commands of vi, emacs, nano, or whatever.

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

Find the files that contain a certain term
Simple use of find and grep to recursively search a directory for files that contain a certain term.

Extract all of the files on an RPM on a non-RPM *nix


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