Commands by katylava (3)

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Summarize the number of open TCP connections by state
Useful for checking the number and state of TCP connections.

Watch how many tcp connections there are per state every two seconds.

remove oprhan package on debian based system

a function to find the fastest free DNS server
Uses GNU Parallel.

count of files from each subfolder
Find the number of files from each folder

Displays user-defined ps output and pidstat output about the top CPU or MEMory users.
It grabs the PID's top resource users with $(ps -eo pid,pmem,pcpu| sort -k 3 -r|grep -v PID|head -10) The sort -k is sorting by the third field which would be CPU. Change this to 2 and it will sort accordingly. The rest of the command is just using diff to display the output of 2 commands side-by-side (-y flag) I chose some good ones for ps. pidstat comes with the sysstat package(sar, mpstat, iostat, pidstat) so if you don't have it, you should. I might should take off the timestamp... :|

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" }

Convert all .flac from a folder subtree in 192Kb mp3
find . -type f -iname '*.flac' # searches from the current folder recursively for .flac audio files | # the output (a .flac audio files with relative path from ./ ) is piped to while read FILE; do FILENAME="${FILE%.*}"; flac -cd "$FILE" | lame -b 192 - "${FILENAME}.mp3"; done # for each line on the list: # FILE gets the file with .flac extension and relative path # FILENAME gets FILE without the .flac extension # run flac for that FILE with output piped to lame conversion to mp3 using 192Kb bitrate

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"

Generate a Google maps URL for GPS location data from digital photo
This command uses the "exiftool" command which is available here: http://www.sno.phy.queensu.ca/~phil/exiftool/ NB, there should be a degree symbol right after the first "%d" NOT a question mark. For some unknown reason, commandlinefu is not able to handle degree symbol correctly ("?")?


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