Commands by vwal (4)

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command! -nargs=1 Vs vs <args>
Because entering ':' requires that you press shift, sometimes common command-line / mini-buffer commands will be capitalized by accident.

List docker volumes by container

Minimize active window
Bind it to some shortcut key, using something like xbindkeys-config (if you do not have xbindkeys: apt-get install xbindkeys xbindkeys-config)

grep tab chars
mixing tabs and spaces for indentation in python would confuse the python interpreter, to avoid that, check if the file has any tab based indentation. "^V" => denotes press control + v and press tab within quotes. $ cat improper_indent.py class Tux(object): print "Hello world.." $ grep " " improper_indent.py print "Hello world.."

Calculate N!
Same as the seq/bc solution but without bc.

check the status of 'dd' in progress (OS X)
"killall -USR1 dd" does not work in OS X for me. However, sending INFO instead of USR1 works.

ls not pattern
Hides some entries from listing.

Check if running in an X session
If you want to display a dialog (using xdialog/kdialog/zenity) you need to make sure that you have a valid X session. Checks for the existence of the DISPLAY variable.

Both view and pipe the file without saving to disk
This is a cool trick to view the contents of the file on /dev/pts/0 (or whatever terminal you're using), and also send the contents of that file to another program by way of an unnamed pipe. All the while, you've not bothered saving any extra data to disk, like you might be tempted to do with sed or grep to filter output.

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" }


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