Commands by chemila (1)

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Prefix every line with a timestamp
Useful to add a timestamp to every line printed to stdout. You can use `-Ins` instead of `-Iseconds` if you want more precision.

find which lines in a file are longer than N characters
Filter out lines of input that contain 72, or fewer, characters. This uses bash only. ${#i} is the number of characters in variable i.

Rename all files which contain the sub-string 'foo', replacing it with 'bar'
Would this command line achieve the desired function? My CLI knowledge is not great so this could certainly be wrong. It is merely a suggestion for more experienced uses to critique. Best wishes roly :-)

convert ascii string to hex
just a bit simpler

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"

HTML5 ogg player
find OGG audio files on your *nix box and listen to them using your web browser

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" }

Display any tcp connections to apache
Sometimes apache will get stuck in an established state where you can't get a list of the connecting IP's from mod_status... not a good thing when you need to ban an abusive ip.

Adding specific CustomLog for each Virtual Domain of Apache

Show webcam output
Show the webcam output with mplayer.

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