Commands using head (314)

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Create a script of the last executed command
Sometimes commands are long, but useful, so it's helpful to be able to make them permanent without having to retype them. An alternative could use the history command, and a cut/sed line that works on your platform. $history -1 | cut -c 7- > foo.sh

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" }

Remove all zero size files from current directory (not recursive)
works only in zsh

Show which programs are listening on TCP ports
Alternative: $ ss -tlpn

list files recursively by size

Stream (almost) any music track in mplayer
Just give it an artist and/or song at the end of the command as shown.

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" }

Burn an audio CD.
My variation on an audio burning command from commandlinefu - this one doesn't crap out if you want to burn a CD in a directory whose permissions don't allow it, and instead rips everything to /tmp. If you mount your music partition like I do using Samba, you probably don't have write permission inside that file system in order to create the temporary directory other audio burning commands here use. Not a bad idea to add cdrom to your groups, and /bin/eject with visudo.

Start a local web server in the current directory on a random dynamic port.

Take screenshot through SSH
When connected to a box via ssh you can do a quick screenshot of that box using this command. After that you can rscp it over to your box and look at it.


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