Commands using man (66)

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Run a command, redirecting output to a file, then edit the file with vim.
This is one of those 'nothing' shell functions ...which I use all the time. If the command contains spaces, it must be quoted, e.g. $ vimcmd 'svn diff' /tmp/svndiff.out If I want to keep the output of the command that I'm running, I use vimcmd. If I don't need to keep the output, I use this: $ vim

Pick a random line from a file
This is from perldoc -q random.*line, which says: This has a significant advantage in space over reading the whole file in. You can find a proof of this method in The Art of Computer Programming, Volume 2, Section 3.4.2, by Donald E. Knuth. Who am I to argue with Don Knuth?

Get current Xorg resolution via xrandr
Not sure if it works the same on any shell.

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" }

Non Numeric Check
use to execute a block of code only if $var is numeric

do a full file listing of every file found with locate

Find the package that installed a command

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"

Wait for an already launched program to stop before starting a new command.
Referring to the original post, if you are using $! then that means the process is a child of the current shell, so you can just use `wait $!`. If you are trying to wait for a process created outside of the current shell, then the loop on `kill -0 $PID` is good; although, you can't get the exit status of the process.

Mute xterm
Disable the annoying beep in xterm


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