Commands by teloon (3)

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Use tagged vlans
Great for sysadmins! Don't forget to pass the vlan to your port in a manageable switch. After vconfig, you should use $sudo ifconfig eth0.[VID] up Now the interface is up, you can use dhclient or ifconfig again to get an ip address.

Find the package that installed a command

seconds since epoch to ISO timestamp
No need to use perl, awk, nor /usr/bin/date -- bash's "printf" builtin will do it.

Compare two CSV files, discarding any repeated lines
The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

I hate `echo X | Y`
apart from not being generalisable to all shells, `Y <<< X` seems nicer to me than `echo X | Y`, e.g. $ <<< lol cat; it reads easier, you type less, and it also looks cool

Play online music videos in terminal
pvl 'link1' 'link2' 'link3' Play Youtube, Vimeo, etc links without visual elements. Great for music videos when you just want the audio. You can control mplayer with this! Hit Ctrl-C twice to exit (if you're playing multiple files)

Loop over the days of a month, in $YYYY$MM$DD format
Edit YYYY and MM at the beginning of the command with the year and month you want. Note that `DD=$(printf "%02d" $d)` will pad single digit integers with a leading zero. Substitute `echo $YYYY$MM$DD` at the end of the line with the command you want to launch, for instance script.pl --yyyymmdd $YYYY$MM$DD Also available on GitHub as bash util: https://github.com/fibo/yyyymmdd

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" }

Listing today’s files only

Make window transparent (50% opacity) in Gnome shell
Click window to change its opacity. Source: https://unix.stackexchange.com/a/494289

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