Commands by kniht (5)

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Find files with lines that do not match a pattern
This one would be much faster, as it's only one executed 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"

Monitoring wifi connection by watch command (refresh every 3s), displaying iw dump info and iwconfig on wireless interface "wlan0"

Print text string vertically, one character per line.

How to remove an ISO image from media database

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" }

Prepend a text to a file.
Prepend text to a file. It doen't need temporary files, ed or sed.

Get IPv4 of eth0 for use with scripts
Simple and easy. No regex, no search and replace. Just clean, built-in tools.

Do a command but skip recording it in the bash command history
Note the extra space before the command (I had to put it as an underscore since the website eats up preceding spaces). That's all it takes. Now if you check your history with "$ history", it wont show up.

Live stream a remote audio device over ssh using only ffmpeg
Change parameter 'plughw:0,0' in accordance with your audio device. To learn 'plughw' option, type the command aplay -l.


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