Commands using cat (514)

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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" }

Speed up or slow down video (and audio)
Usage: videospeed video_filename speedchange newfilename videospeed foo.mp4 0.5 foo_slow.mp4 Range of 0.5 (50%) - 2.0 (200%) is valid.

Returns the number of cores in a linux machine.
Original article in http://www.howtogeek.com/howto/ubuntu/display-number-of-processors-on-linux/

Extract title from HTML files
previous version leaves lots of blank lines

Colorized JSON pretty printing
Uses pygmentize and python to create indented and colorized JSON output

Graphical tree of sub-directories with files
The command finds every item within the directory and edits the output so that subdirectories are and files are output much like the tree command

Compare two CSV files, discarding any repeated lines
The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

list files recursively by size

Recursively grep thorugh directory for string in file.
Print line numbers also, so you don't have to search through the files once its open for the string you already grepped for.

Display full tree information of a single process


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