Commands by DavidLudwig (1)

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Content search.
Grep will read the contents of each file in PWD and will use the REs $1 $2 ... $n to match the contents. In case of match, grep will print the appropriate file, line number and the matching line. It's just easier to write $ ff word1 word2 word3 Instead of $ grep -rinE 'word1|word2|word3' .

Continue a current job in the background

Show memory usage of all docker / lxc containers

List empty any directories

tail: watch a filelog
-f file(s) to be monitorized -n number of last line to be printed on the screen in this example, the content of two files are displayed

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" }

list block devices
Shows all block devices in a tree with descruptions of what they are.

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

Delete Empty Directories
Deletes empty directories and prints an error if directory is not empty.

check open ports without netstat or lsof


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